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<div id="header">
<h1>Ccache news</h1>
<div class="details">
<span id="revnumber">version 4.7.4</span>
</div>
<div id="toc" class="toc2">
<div id="toctitle">Table of Contents</div>
<ul class="sectlevel1">
<li><a href="#_ccache_4_7_4">Ccache 4.7.4</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes">Bug fixes</a></li>
<li><a href="#_other_minor_improvements">Other minor improvements</a></li>
<li><a href="#_documentation_improvements">Documentation improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_7_3">Ccache 4.7.3</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_improvements">New features and improvements</a></li>
<li><a href="#_bug_fixes_2">Bug fixes</a></li>
<li><a href="#_other_minor_improvements_2">Other minor improvements</a></li>
<li><a href="#_documentation_improvements_2">Documentation improvements</a></li>
<li><a href="#_test_improvements">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_7_2">Ccache 4.7.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_3">Bug fixes</a></li>
<li><a href="#_build_improvements">Build improvements</a></li>
<li><a href="#_test_improvements_2">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_7_1">Ccache 4.7.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_4">Bug fixes</a></li>
<li><a href="#_build_improvements_2">Build improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_7">Ccache 4.7</a>
<ul class="sectlevel2">
<li><a href="#_compatibility_notes">Compatibility notes</a></li>
<li><a href="#_changed_tooling">Changed tooling</a></li>
<li><a href="#_new_and_improved_features">New and improved features</a></li>
<li><a href="#_removed_features">Removed features</a></li>
<li><a href="#_bug_fixes_5">Bug fixes</a></li>
<li><a href="#_build_improvements_3">Build improvements</a></li>
<li><a href="#_test_improvements_3">Test improvements</a></li>
<li><a href="#_documentation_improvements_3">Documentation improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_6_3">Ccache 4.6.3</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_6">Bug fixes</a></li>
<li><a href="#_build_improvements_4">Build improvements</a></li>
<li><a href="#_test_improvements_4">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_6_2">Ccache 4.6.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_7">Bug fixes</a></li>
<li><a href="#_build_improvements_5">Build improvements</a></li>
<li><a href="#_test_improvements_5">Test improvements</a></li>
<li><a href="#_documentation_improvements_4">Documentation improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_6_1">Ccache 4.6.1</a>
<ul class="sectlevel2">
<li><a href="#_new_features">New features</a></li>
<li><a href="#_bug_fixes_8">Bug fixes</a></li>
<li><a href="#_build_improvements_6">Build improvements</a></li>
<li><a href="#_test_improvements_6">Test improvements</a></li>
<li><a href="#_documentation_improvements_5">Documentation improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_6">Ccache 4.6</a>
<ul class="sectlevel2">
<li><a href="#_new_features_2">New features</a></li>
<li><a href="#_bug_fixes_9">Bug fixes</a></li>
<li><a href="#_documentation_improvements_6">Documentation improvements</a></li>
<li><a href="#_test_improvements_7">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_5_1">Ccache 4.5.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_10">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_4_5">Ccache 4.5</a>
<ul class="sectlevel2">
<li><a href="#_new_features_3">New features</a></li>
<li><a href="#_compatibility_notes_2">Compatibility notes</a></li>
<li><a href="#_bug_fixes_11">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_4_4_2">Ccache 4.4.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_12">Bug fixes</a></li>
<li><a href="#_test_improvements_8">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_4_1">Ccache 4.4.1</a>
<ul class="sectlevel2">
<li><a href="#_new_features_4">New features</a></li>
<li><a href="#_bug_fixes_13">Bug fixes</a></li>
<li><a href="#_build_improvements_7">Build improvements</a></li>
<li><a href="#_test_improvements_9">Test improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_4">Ccache 4.4</a>
<ul class="sectlevel2">
<li><a href="#_new_features_5">New features</a></li>
<li><a href="#_bug_fixes_14">Bug fixes</a></li>
<li><a href="#_changed_tooling_2">Changed tooling</a></li>
<li><a href="#_buildtestdocumentation_improvements">Build/test/documentation improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_3">Ccache 4.3</a>
<ul class="sectlevel2">
<li><a href="#_new_features_6">New features</a></li>
<li><a href="#_bug_fixes_15">Bug fixes</a></li>
<li><a href="#_build_improvements_8">Build improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_4_2_1">Ccache 4.2.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_16">Bug fixes</a></li>
<li><a href="#_portability_and_build_improvements">Portability and build improvements</a></li>
<li><a href="#_documentation">Documentation</a></li>
</ul>
</li>
<li><a href="#_ccache_4_2">Ccache 4.2</a>
<ul class="sectlevel2">
<li><a href="#_new_features_7">New features</a></li>
<li><a href="#_bug_fixes_17">Bug fixes</a></li>
<li><a href="#_portability_and_build_improvements_2">Portability and build improvements</a></li>
<li><a href="#_documentation_2">Documentation</a></li>
</ul>
</li>
<li><a href="#_ccache_4_1">Ccache 4.1</a>
<ul class="sectlevel2">
<li><a href="#_new_features_8">New features</a></li>
<li><a href="#_bug_fixes_18">Bug fixes</a></li>
<li><a href="#_portability_and_build_fixes">Portability and build fixes</a></li>
<li><a href="#_other_improvements_and_fixes">Other improvements and fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_4_0">Ccache 4.0</a>
<ul class="sectlevel2">
<li><a href="#_summary_of_major_changes">Summary of major changes</a></li>
<li><a href="#_compatibility_notes_3">Compatibility notes</a></li>
<li><a href="#_changed_tooling_3">Changed tooling</a></li>
<li><a href="#_detailed_functional_changes">Detailed functional changes</a></li>
<li><a href="#_other_improvements">Other improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_12">Ccache 3.7.12</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_19">Bug fixes</a></li>
<li><a href="#_other">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_11">Ccache 3.7.11</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_20">Bug fixes</a></li>
<li><a href="#_other_2">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_10">Ccache 3.7.10</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_21">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_9">Ccache 3.7.9</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_22">Bug fixes</a></li>
<li><a href="#_other_3">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_8">Ccache 3.7.8</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_23">Bug fixes</a></li>
<li><a href="#_other_4">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_7">Ccache 3.7.7</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_24">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_6">Ccache 3.7.6</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_25">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_5">Ccache 3.7.5</a>
<ul class="sectlevel2">
<li><a href="#_new_features_9">New features</a></li>
<li><a href="#_bug_fixes_26">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_4">Ccache 3.7.4</a>
<ul class="sectlevel2">
<li><a href="#_improvements">Improvements</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_3">Ccache 3.7.3</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_27">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_2">Ccache 3.7.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_28">Bug fixes</a></li>
<li><a href="#_documentation_3">Documentation</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7_1">Ccache 3.7.1</a>
<ul class="sectlevel2">
<li><a href="#_changes">Changes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_7">Ccache 3.7</a>
<ul class="sectlevel2">
<li><a href="#_changes_2">Changes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_6">Ccache 3.6</a>
<ul class="sectlevel2">
<li><a href="#_changes_3">Changes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_5_1">Ccache 3.5.1</a>
<ul class="sectlevel2">
<li><a href="#_changes_4">Changes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_5">Ccache 3.5</a>
<ul class="sectlevel2">
<li><a href="#_changes_5">Changes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_4_3">Ccache 3.4.3</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_29">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_4_2">Ccache 3.4.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_30">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_4_1">Ccache 3.4.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_31">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_4">Ccache 3.4</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements">New features and enhancements</a></li>
<li><a href="#_bug_fixes_32">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_6">Ccache 3.3.6</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_2">New features and enhancements</a></li>
<li><a href="#_bug_fixes_33">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_5">Ccache 3.3.5</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_3">New features and enhancements</a></li>
<li><a href="#_bug_fixes_34">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_4">Ccache 3.3.4</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_4">New features and enhancements</a></li>
<li><a href="#_bug_fixes_35">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_3">Ccache 3.3.3</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_36">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_2">Ccache 3.3.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_37">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3_1">Ccache 3.3.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_38">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_3">Ccache 3.3</a>
<ul class="sectlevel2">
<li><a href="#_notes">Notes</a></li>
<li><a href="#_new_features_and_enhancements_5">New features and enhancements</a></li>
<li><a href="#_bug_fixes_39">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_9">Ccache 3.2.9</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_40">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_8">Ccache 3.2.8</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_41">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_7">Ccache 3.2.7</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_42">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_6">Ccache 3.2.6</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_43">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_5">Ccache 3.2.5</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_6">New features and enhancements</a></li>
<li><a href="#_bug_fixes_44">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_4">Ccache 3.2.4</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_45">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_3">Ccache 3.2.3</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_7">New features and enhancements</a></li>
<li><a href="#_bug_fixes_46">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_2">Ccache 3.2.2</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_8">New features and enhancements</a></li>
<li><a href="#_bug_fixes_47">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2_1">Ccache 3.2.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_48">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_2">Ccache 3.2</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_9">New features and enhancements</a></li>
<li><a href="#_bug_fixes_49">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_12">Ccache 3.1.12</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_50">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_11">Ccache 3.1.11</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_51">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_10">Ccache 3.1.10</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_10">New features and enhancements</a></li>
<li><a href="#_bug_fixes_52">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_9">Ccache 3.1.9</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_53">Bug fixes</a></li>
<li><a href="#_other_5">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_8">Ccache 3.1.8</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_11">New features and enhancements</a></li>
<li><a href="#_bug_fixes_54">Bug fixes</a></li>
<li><a href="#_other_6">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_7">Ccache 3.1.7</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_55">Bug fixes</a></li>
<li><a href="#_other_7">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_6">Ccache 3.1.6</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_12">New features and enhancements</a></li>
<li><a href="#_bug_fixes_56">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_5">Ccache 3.1.5</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_13">New features and enhancements</a></li>
<li><a href="#_bug_fixes_57">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_4">Ccache 3.1.4</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_58">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_3">Ccache 3.1.3</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_59">Bug fixes</a></li>
<li><a href="#_other_8">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_2">Ccache 3.1.2</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_60">Bug fixes</a></li>
<li><a href="#_other_9">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1_1">Ccache 3.1.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_61">Bug fixes</a></li>
<li><a href="#_other_10">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_1">Ccache 3.1</a>
<ul class="sectlevel2">
<li><a href="#_new_features_and_enhancements_14">New features and enhancements</a></li>
<li><a href="#_bug_fixes_62">Bug fixes</a></li>
<li><a href="#_other_11">Other</a></li>
</ul>
</li>
<li><a href="#_ccache_3_0_1">Ccache 3.0.1</a>
<ul class="sectlevel2">
<li><a href="#_bug_fixes_63">Bug fixes</a></li>
</ul>
</li>
<li><a href="#_ccache_3_0">Ccache 3.0</a>
<ul class="sectlevel2">
<li><a href="#_general">General</a></li>
<li><a href="#_upgrade_notes">Upgrade notes</a></li>
<li><a href="#_new_features_and_enhancements_15">New features and enhancements</a></li>
<li><a href="#_bug_fixes_64">Bug fixes</a></li>
</ul>
</li>
</ul>
</div>
</div>
<div id="content">
<div class="sect1">
<h2 id="_ccache_4_7_4"><a class="anchor" href="#_ccache_4_7_4"></a>Ccache 4.7.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-11-21</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes"><a class="anchor" href="#_bug_fixes"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed an inode cache race condition.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The default temporary directory is now <code>$XDG_RUNTIME_DIR/ccache-tmp</code> instead
of a hardcoded <code>/run/user/&lt;UID&gt;/ccache-tmp</code>. If <code>XDG_RUNTIME_DIR</code> is not set,
<code>&lt;cache_dir&gt;/tmp</code> is used. This avoids creating <code>/run/user/&lt;UID&gt;</code> on systems
that don&#8217;t have it if compiling as root.<br>
<span class="small"><em>[contributed by Joel Rosdahl and Oleg Sidorkin]</em></span></p>
</li>
<li>
<p>Added a fallback in case <code>posix_fallocate</code> returns <code>EINVAL</code> when creating the
inode cache file.<br>
<span class="small"><em>[contributed by Oleg Sidorkin]</em></span></p>
</li>
<li>
<p>Connection timeout for an HTTP connection is now reported as a timeout instead
of an error.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Temporary files found in the cache are no longer counted in
<code>--show-compression</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Removed duplicate magic header in output from <code>--inspect</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Ccache now properly waits for all recompression jobs to finish when there is
no <code>f</code> subdirectory in the cache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_minor_improvements"><a class="anchor" href="#_other_minor_improvements"></a>Other minor improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Improved inode cache logging.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements"><a class="anchor" href="#_documentation_improvements"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Removed stray parenthesis.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved description of how header files are handled.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a hint about using <code>-fno-pch-timestamp</code> for precompiled headers with
Clang.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Removed obsolete description of compiler type &#8220;pump&#8221;.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_7_3"><a class="anchor" href="#_ccache_4_7_3"></a>Ccache 4.7.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-11-05</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_improvements"><a class="anchor" href="#_new_features_and_improvements"></a>New features and improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Re-added support for handling a <code>-Wp,-MD</code> or <code>-Wp,-MMD</code> option with <code>-o</code> but
without <code>-MMD</code>, <code>-MQ</code> or <code>-MT</code> for GCC and Clang. (This combination of options
is used by the Linux kernel build system and became unsupported as a
side-effect of a feature added in ccache 4.7.)<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Variables that affect Clang version on macOS are now added to the input
hash.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Variables that affect the underlying compiler used by ICC (the Intel compiler)
are now added to the input hash.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_2"><a class="anchor" href="#_bug_fixes_2"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed parsing of sloppiness with a trailing delimiter.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_minor_improvements_2"><a class="anchor" href="#_other_minor_improvements_2"></a>Other minor improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Removed a redundant slash in URLs when querying remote HTTP storage.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved logging related to the inode cache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements_2"><a class="anchor" href="#_documentation_improvements_2"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Added documentation of the default value of <strong>keep_comments_cpp</strong>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements"><a class="anchor" href="#_test_improvements"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Silenced various benign test warnings.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_7_2"><a class="anchor" href="#_ccache_4_7_2"></a>Ccache 4.7.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-10-29</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_3"><a class="anchor" href="#_bug_fixes_3"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a problem when using 32-bit and 64-bit ccache binaries with the same
inode cache file.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Ccache now processes the argument following a <code>-Xarch</code> option.<br>
<span class="small"><em>[contributed by an anonymous user]</em></span></p>
</li>
<li>
<p>Made sure to use the configured umask for command line operations like
<code>--zero-stats</code> so that newly created cache directories will have correct
permissions.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements"><a class="anchor" href="#_build_improvements"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Include <code>limits.h</code> for <code>PATH_MAX</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_2"><a class="anchor" href="#_test_improvements_2"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Disabled flaky Windows profiling tests.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_7_1"><a class="anchor" href="#_ccache_4_7_1"></a>Ccache 4.7.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-10-22</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_4"><a class="anchor" href="#_bug_fixes_4"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression in 4.7 related to using the <code>-MD</code> or <code>-MMD</code> option when
compiling an assembler file.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_2"><a class="anchor" href="#_build_improvements_2"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for compiling ccache with GCC 8.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Removed unneeded C++11 flag in libatomic test.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_7"><a class="anchor" href="#_ccache_4_7"></a>Ccache 4.7</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-10-17</p>
</div>
<div class="sect2">
<h3 id="_compatibility_notes"><a class="anchor" href="#_compatibility_notes"></a>Compatibility notes</h3>
<div class="ulist">
<ul>
<li>
<p>The cache entry format has changed, so ccache 4.7 will not share cache entries
with earlier versions. Different ccache versions can however still use the
same cache storage without any issues.</p>
</li>
<li>
<p>The <a href="https://ccache.dev/manual/4.7.html#config_cache_dir">default location of
the cache directory</a> on Windows has been changed from <code>%APPDATA%\ccache</code> to
<code>%LOCALAPPDATA%\ccache</code>. Please remove any existing <code>%APPDATA%\ccache</code>
directory or move it to <code>%LOCALAPPDATA%\ccache</code> to keep it.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_changed_tooling"><a class="anchor" href="#_changed_tooling"></a>Changed tooling</h3>
<div class="ulist">
<ul>
<li>
<p>A C++17 compiler and CMake 3.15 or newer are now required to
build ccache.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_new_and_improved_features"><a class="anchor" href="#_new_and_improved_features"></a>New and improved features</h3>
<div class="ulist">
<ul>
<li>
<p>The <a href="https://ccache.dev/manual/4.7.html#config_inode_cache">inode cache</a> is now
enabled by default, but only if the filesystem where ccache&#8217;s temporary
directory is located is known to work with the inode cache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved performance of cache entry reading and writing.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a <a href="https://ccache.dev/manual/4.7.html#config_remote_only"><strong>remote_only</strong></a>
configuration option, which tells ccache to disable local storage. This way,
ccache can use a shared
<a href="https://ccache.dev/manual/4.7.html#_remote_storage_backends">network cache</a>
without writing cache entries locally, which can be useful if the local
storage is ephemeral.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Renamed configuration option <strong>secondary_storage</strong> to
<a href="https://ccache.dev/manual/4.7.html#config_remote_storage"><strong>remote_storage</strong></a>.
The old spelling will still work as a deprecated alias.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved handling of manifests when using both local and remote storage.</p>
<div class="paragraph">
<p>On a cache miss, ccache used to update the local manifest file and write it to
remote storage, thereby overwriting any preexisting manifest entries on remote
storage. Similarly, the local manifest could be replaced by the remote manifest
on a remote cache hit, thus discarding local entries. This has now been improved
so that ccache will merge local and remote manifest entries transparently.<br>
<span class="small"><em>[contributed by Joel Rosdahl and an anonymous user]</em></span></p>
</div>
</li>
<li>
<p>Added support for caching assembler listing files with compiler option
<code>-Wa,-a=file</code>. This also fixes a bug in ccache 4.6.2+ where usage of
<code>-Wa,-march=&#8230;&#8203;</code> makes ccache fall back to running the compiler.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved statistics shown by <code>ccache --show-stats</code>. Most values are now shown
in relation to a total count, and some less useful statistics counters have
been changed to be displayed only with <code>--verbose</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved statistics for remote hits and misses.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Renamed &#8220;Primary config&#8221; to &#8220;Config file&#8221; and &#8220;Secondary config&#8221; to
&#8220;System config file&#8221; in the output of <code>ccache --show-stats --verbose</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added support for
<a href="https://ccache.dev/manual/4.7.html#_run_modes">masquerading as a
compiler</a> via a copy or hard link of the ccache executable. Previously, ccache
only supported masquerading as a compiler by using a symbolic link.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>A timestamp is now included in
<a href="https://ccache.dev/manual/4.7.html#_cache_debugging">per-object
debug filenames</a>. This makes it easier to compare two builds without having to
save previous debug files before the second build. It also makes sure debug
files won&#8217;t be overwritten if an object file is compiled several times during
one build.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added support for Clang&#8217;s <code>--</code> option.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Cache entries are now shared for different <code>-MT</code>/<code>-MQ</code> options.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The <a href="https://ccache.dev/manual/4.7.html#config_cache_dir">default location of
the cache directory</a> on Windows has been changed to <code>%LOCALAPPDATA%\ccache</code>,
both in Windows Bash and Windows native environments such as CMD or
Powershell.</p>
<div class="paragraph">
<p>Previous ccache versions defaulted to storing the cache in <code>%APPDATA%\ccache</code> on
Windows in native environment (i.e., when the <code>%USER%</code> variable was not set),
which could result in large network file transfers of the cache in domain
environments and similar problems.<br>
<span class="small"><em>[contributed by Rafael Kitover]</em></span></p>
</div>
</li>
<li>
<p>Ccache now uses subsecond resolution timestamps when checking for &#8220;too new
include files&#8221;. In practice, this means that the direct mode will no longer
be disabled for newly generated include files.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Started using subsecond resolution timestamps in manifest files. This improves
accuracy with <strong>file_stat_matches</strong>
<a href="https://ccache.dev/manual/4.7.html#config_sloppiness">sloppiness</a>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added support for subsecond timestamps on macOS.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added <a href="https://ccache.dev/manual/4.7.html#_the_depend_mode">depend
mode</a> support for MSVC.<br>
<span class="small"><em>[contributed by Orgad Shaneh and Luboš Luňák]</em></span></p>
</li>
<li>
<p>Added support for the Intel compiler on Windows.<br>
<span class="small"><em>[contributed by Daniel Richtmann]</em></span></p>
</li>
<li>
<p>Ccache now sets <code>CCACHE_DISABLE</code> when running the compiler. This avoids
running ccache twice (and potentially storing two different results in the
cache) if, for instance, the compiler happens to be a wrapper script that in
turn runs <code>ccache $compiler &#8230;&#8203;</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added support for Redis over Unix sockets.<br>
<span class="small"><em>[contributed by Anders F Björklund]</em></span></p>
</li>
<li>
<p>Added support for GCC&#8217;s <code>-fprofile-abs-path</code> option by including the current
working directory in the input hash. To opt out of this, set <strong>gcno_cwd</strong>
<a href="https://ccache.dev/manual/4.7.html#config_sloppiness">sloppiness</a>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made it possible to exclude <code>-frandom-seed=<em>seed</em></code> options from the input hash
with a new <strong>random_seed</strong>
<a href="https://ccache.dev/manual/4.7.html#config_sloppiness">sloppiness</a>.<br>
<span class="small"><em>[contributed by Raihaan Shouhell]</em></span></p>
</li>
<li>
<p>Added support for server name in
<a href="https://ccache.dev/manual/4.7.html#_file_storage_backend">remote
storage file URLs</a> on Windows.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Configuration file locations are now included in the
<a href="https://ccache.dev/manual/4.7.html#_cache_debugging">debug log</a>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The inode cache file is no longer removed with <code>ccache --clear</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Result format version and number of files are now printed when inspecting a
result cache entry file.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_removed_features"><a class="anchor" href="#_removed_features"></a>Removed features</h3>
<div class="ulist">
<ul>
<li>
<p>Removed the <strong>share-hits</strong> attribute for remote storage. It has been superseded
by the <a href="https://ccache.dev/manual/4.7.html#config_remote_only"><strong>remote_only</strong></a>
configuration option.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Buggy support for GCC-specific environment variables <code>DEPENDENCIES_OUTPUT</code> and
<code>SUNPRO_DEPENDENCIES</code> has been removed. If any of those variables are set,
ccache now just falls back to running the real compiler.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_5"><a class="anchor" href="#_bug_fixes_5"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The correct dependency target will now be produced even when a
<a href="https://ccache.dev/manual/4.7.html#config_base_dir">base directory</a> is used&#8201;&#8212;&#8201;the dependency target will still be an absolute path.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed a bug that could lead to bad modification timestamp (mtime) for object
files on systems that lack <code>utimensat</code> and <code>utimes</code> system calls (such as
Windows).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed ordering of MSVC include directory options when using
<code>/external:I&lt;directory&gt;</code>.<br>
<span class="small"><em>[contributed by Raihaan Shouhell]</em></span></p>
</li>
<li>
<p>Fixed capturing of MSVC stdout/stderr when running from Visual Studio.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Carriage return characters are now retained in the compiler output on
Windows.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Made sure not to increment the &#8220;preprocessed_cache_miss&#8221; counter in recache
mode.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed an issue with the inode cache in combination with
<code>__DATE__</code>/<code>__TIME__</code>/<code>__TIMESTAMP__</code> macros in the source code.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made sure to enable the inode cache only if subsecond timestamps are
available.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Cache entries created with enabled hard linking or file cloning are no longer
written to remote storage since they won&#8217;t be possible to retrieve correctly
anyway.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Ccache now accepts spaces between target and colon when parsing dependency
files in the depend mode.<br>
<span class="small"><em>[contributed by Louis Caron]</em></span></p>
</li>
<li>
<p>Fixed a crash when failing to write an error message to stderr after failing
to write to the log file.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made ccache able to retrieve an object file from the cache even if the
destination object file exists and is read-only.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The <code>.exe</code> extension is now stripped from the ccache executable name in
<code>ccache --version</code> on Windows. <br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Fixed naming of temporary files written to the cache directory.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_3"><a class="anchor" href="#_build_improvements_3"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Enabled static runtime linking for MSVC.<br>
<span class="small"><em>[contributed by Cristian Adam and Rafael Kitover]</em></span></p>
</li>
<li>
<p>The Zstandard and Hiredis dependencies are now by default downloaded from the
Internet when unavailable.<br>
<span class="small"><em>[contributed by Rafael Kitover]</em></span></p>
</li>
<li>
<p>Added support for pkgconfig to find a Zstandard installation.<br>
<span class="small"><em>[contributed by Rosen Penev]</em></span></p>
</li>
<li>
<p>Removed usage of the deprecated <code>codecvt</code> header.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Added headers to CMake project files.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_3"><a class="anchor" href="#_test_improvements_3"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Made the integration tests work on Windows.<br>
<span class="small"><em>[contributed by Orgad Shaneh and R. Voggenauer]</em></span></p>
</li>
<li>
<p>Improved diagnostics from the &#8220;Version output readable&#8221; test.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Made setting the <code>KEEP_TESTDIR</code> variable actually work.<br>
<span class="small"><em>[contributed by Louis Caron]</em></span></p>
</li>
<li>
<p>Fixed a typo in depend mode tests.<br>
<span class="small"><em>[contributed by Louis Caron]</em></span></p>
</li>
<li>
<p>Added more depend mode tests.<br>
<span class="small"><em>[contributed by Louis Caron]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements_3"><a class="anchor" href="#_documentation_improvements_3"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Improved the
<a href="https://github.com/ccache/ccache/blob/v4.7/doc/INSTALL.md">installation
guide</a>.<br>
<span class="small"><em>[contributed by Rafael Kitover]</em></span></p>
</li>
<li>
<p>Fixed a typo in the help text.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_6_3"><a class="anchor" href="#_ccache_4_6_3"></a>Ccache 4.6.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-08-27</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_6"><a class="anchor" href="#_bug_fixes_6"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed MSVC support (regression in ccache 4.6.2).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed detection of PCH header for concatenated <code>-include</code> option (e.g.,
<code>-includepch.h</code> instead of <code>-include pch.h</code>).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_4"><a class="anchor" href="#_build_improvements_4"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed build with musl when using GCC 12.<br>
<span class="small"><em>[contributed by Khem Raj]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_4"><a class="anchor" href="#_test_improvements_4"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Disabled the &#8220;Failure to write output file&#8221; test when running on a
filesystem that doesn&#8217;t support read-only directories.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_6_2"><a class="anchor" href="#_ccache_4_6_2"></a>Ccache 4.6.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-08-22</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_7"><a class="anchor" href="#_bug_fixes_7"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a race condition that could lead to a crash if a file in the cache is
removed with unlucky timing, e.g. by another ccache process doing cache
cleanup.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Dependency file rewriting will now always be performed if
<code>base_dir</code>/<code>CCACHE_BASEDIR</code> is active. This fixes a problem with the
dependency file content when Clang is used with <code>-fsanitize=address</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed handling of error condition for <code>--hash-file</code>/<code>--checksum-file</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made sure to enable the inode cache only if subsecond <code>stat</code> timestamps are
available.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a work-around for a Clang bug when writing to a full NFS file system.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made failure writing to the output file increment the &#8220;bad output file&#8221;
counter instead of &#8220;cache miss&#8221;.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed false positive cache hits for code constructions similar to
<code><em>asm</em>(".incbin" " \"file\"")</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed false success for <code>-fcolor-diagnostics</code> probe with GCC. A side effect of
this is that a compiler type that ccache can&#8217;t identify from the compiler name
(such as <code>/usr/bin/cc</code> where <code>cc</code> is not a symlink) from now on won&#8217;t produce
color diagnostics when used via ccache even if the compiler actually is GCC or
Clang.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>More cases of invalid secondary storage URLs are now handled gracefully.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed the display of maximum cache size in <code>ccache -s</code> if it&#8217;s 0 (=
unlimited).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Removed AsciiDoc markup from help text of <code>--trim-dir</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The temporary directory is now cleaned up properly even if it&#8217;s left
unconfigured.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made cleanup of the temporary directory not rely a directory timestamp.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made sure to retain mtime/atime when recompressing cache files with
<code>-X</code>/<code>--recompress</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The correct umask is now used when populating the primary cache from a
secondary cache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed creation of temporary files on file systems that don&#8217;t support hard
links (such as FAT32).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added knowledge about <code>-Wa,&#8230;&#8203;=file</code> so that ccache then falls back to running
the real compiler.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Corrected handling of space in paths when using response file on Windows.<br>
<span class="small"><em>[contributed by Sergey Semushin]</em></span></p>
</li>
<li>
<p>Fixed crash due to empty include filename in preprocessor output generated by
<code>f2c</code>.<br>
<span class="small"><em>[contributed by Oleg Sidorkin]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_5"><a class="anchor" href="#_build_improvements_5"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed build problems with a development version of GCC 13.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed build problems with MSVC.<br>
<span class="small"><em>[contributed by Florin Trofin]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_5"><a class="anchor" href="#_test_improvements_5"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Clang warnings from the &#8220;-fdebug-prefix-map&#8221; test are now suppressed.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made sure to only run the &#8220;-ftest-coverage + -fprofile-dir&#8221; test with GCC.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed printing of error messages with embedded newlines.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed warning when running the &#8220;inode_cache&#8221; test in isolation.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed test failure when the compiler used for testing is an old ccache version
masquerading as the compiler.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements_4"><a class="anchor" href="#_documentation_improvements_4"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Mentioned that mtime is used for LRU cleanup.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_6_1"><a class="anchor" href="#_ccache_4_6_1"></a>Ccache 4.6.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-05-15</p>
</div>
<div class="sect2">
<h3 id="_new_features"><a class="anchor" href="#_new_features"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for passing a directory to the MSVC <code>/Fo</code> option.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Added knowledge about the <code>-imsvc</code> compiler option.<br>
<span class="small"><em>[contributed by Jacob Young]</em></span></p>
</li>
<li>
<p>Added knowledge about the <code>-z</code> linker option.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_8"><a class="anchor" href="#_bug_fixes_8"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Improved handling of <code>.gcno</code> files in combination with absolute input file
paths.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Adapted to changes in GCC 9+ <code>.gcno</code> files, which contain the current working
directory, by including said directory in the hash. You can opt out of this by
enabling &#8220;gcno_cwd sloppiness&#8221;.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>A preexisting object file is no longer considered when using
<code>-fsyntax-only</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Authenticate with Redis before database selection.<br>
<span class="small"><em>[contributed by an anonymous user]</em></span></p>
</li>
<li>
<p>Don&#8217;t exit with an error on failure reading a cached file.<br>
<span class="small"><em>[contributed by an anonymous user]</em></span></p>
</li>
<li>
<p>Bail out on too hard MSVC environment variables <code>CL</code> and <code>_CL_</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Only use <code>/run/user/&lt;UID&gt;/ccache-tmp</code> as the temporary directory if it&#8217;s
writable.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed handling of the final newline in cached standard output from the
compiler.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Fixed a bug related to distcc markers in standard error output.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Paths to <code>base_dir</code> are now properly normalized on Windows.<br>
<span class="small"><em>[contributed by Vili Väinölä and Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed handling of MSVC <code>/Fp</code> and <code>/Yu</code> options with concatenated path.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed &#8220;Multiple precompiled headers used&#8221; error if MSVC <code>/Yu</code> option is used
after <code>/Fp</code>.<br>
<span class="small"><em>[contributed by Alexey Telishev]</em></span></p>
</li>
<li>
<p>Check for short reads when reading strings in result/manifest files.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Log expanded secondary storage URL in put/remove.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed logging of statistics counters with value higher than one in debug log
and stats log.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Avoid incorrect error log message for Redis write operations in <code>reshare</code>
mode.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Support Redis URL without host (meaning localhost).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_6"><a class="anchor" href="#_build_improvements_6"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Prefer CMake find module for hiredis and zstd packages.<br>
<span class="small"><em>[contributed by Cristian Adam and Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed building and linking BLAKE3 with MSVC.<br>
<span class="small"><em>[contributed by Rafael Kitover]</em></span></p>
</li>
<li>
<p>Fixed static linkage with hiredis on Windows.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Fixed miscompile of nonstd::expected on MSVC v19.22.<br>
<span class="small"><em>[contributed by Jacob Young]</em></span></p>
</li>
<li>
<p>Fixed build arguments to clang-cl.<br>
<span class="small"><em>[contributed by Jacob Young]</em></span></p>
</li>
<li>
<p>Fixed parsing of MSVC response files. <br>
<span class="small"><em>[contributed by Jacob Young]</em></span></p>
</li>
<li>
<p>Support Git 1.x when determining ccache version.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_6"><a class="anchor" href="#_test_improvements_6"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Worked around an endianness problem which affected builds and tests on
big-endian systems.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>A C++-capable compiler is no longer required for the test suite.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed an issue with inode cache tests, leading to sporadic failures in the
inode test suite when running many parallel tests.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed sporadic failures in the profiling test suite.<br>
<span class="small"><em>[contributed by Jacob Young]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements_5"><a class="anchor" href="#_documentation_improvements_5"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Added reference to example build configs in installation instructions.<br>
<span class="small"><em>[contributed by an anonymous user]</em></span></p>
</li>
<li>
<p>Default cache locations are now mentioned for Windows and macOS as well.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a warning about usage of <code>base_dir</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_6"><a class="anchor" href="#_ccache_4_6"></a>Ccache 4.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2022-02-27</p>
</div>
<div class="sect2">
<h3 id="_new_features_2"><a class="anchor" href="#_new_features_2"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for caching calls to Microsoft Visual C++ (MSVC) and clang-cl
(MSVC compatibility for Clang).<br>
<span class="small"><em>[contributed by Cristian Adam, Luboš Luňák, Orgad Shaneh and Joel
Rosdahl]</em></span></p>
</li>
<li>
<p>Added an option to use a bearer token with the HTTP backend. This makes it
possible to use e.g. Google Cloud Storage as a secondary storage backend.<br>
<span class="small"><em>[contributed by an anonymous user]</em></span></p>
</li>
<li>
<p>Added support for caching standard output from the compiler.<br>
<span class="small"><em>[contributed by Luboš Luňák and Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a new <code>--inspect</code> option for debugging cache entries, replacing the
previous <code>--dump-manifest</code> and <code>--dump-result</code> options.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Enabled HTTP keep-alive by default.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_9"><a class="anchor" href="#_bug_fixes_9"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed copying of binary files on Windows.<br>
<span class="small"><em>[contributed by R. Voggenauer]</em></span></p>
</li>
<li>
<p>Improved detection of the <code>.incbin</code> assembler directive to reduce false
positives.<br>
<span class="small"><em>[contributed by Alexey Sheplyakov]</em></span></p>
</li>
<li>
<p>Ccache now verifies that <code>/run/user/&lt;UID&gt;/ccache-tmp</code> is writable before using
it for temporary files.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed statistics output for secondary storage.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
<li>
<p>Fixed a problem when copying a cache entry from secondary storage into an
empty primary storage.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Visual Studio .rsp files with UTF-16LE encoding are now handled correctly.<br>
<span class="small"><em>[contributed by Vili Väinölä]</em></span></p>
</li>
<li>
<p>Made conversion to relative paths more reliable on Windows.<br>
<span class="small"><em>[contributed by Marius Zwicker]</em></span></p>
</li>
<li>
<p>The process umask is now respected when making hard linked files read only.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>A forced recache is no longer considered a &#8220;direct cache miss&#8221;.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_improvements_6"><a class="anchor" href="#_documentation_improvements_6"></a>Documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Corrected reference to the <code>debug_dir</code> option.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved documentation of <code>--config-path</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added documentation that compiler plugins are hashed too.<br>
<span class="small"><em>[contributed by Philipp Gortan]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_7"><a class="anchor" href="#_test_improvements_7"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>The &#8220;trim_dir&#8221; test suite is now only run when cleanup tests are enabled.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_5_1"><a class="anchor" href="#_ccache_4_5_1"></a>Ccache 4.5.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-11-17</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_10"><a class="anchor" href="#_bug_fixes_10"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed entry_size field for result entries. This bug affected the recompression
feature (<code>-X</code>/<code>--recompress</code>) in ccache 4.5.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>The actual compression level is now once again stored in the cache entry
header.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Corrected error handling for non-constructible secondary storage backends. For
instance, this avoids a crash when a Redis server can&#8217;t be reached.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_5"><a class="anchor" href="#_ccache_4_5"></a>Ccache 4.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-11-13</p>
</div>
<div class="sect2">
<h3 id="_new_features_3"><a class="anchor" href="#_new_features_3"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Made various improvements to the cache entry format. Among other things, the
header now contains a creation timestamp and a note of the ccache version used
to create the entry. The cache entry checksum has also been upgraded to use
128-bit XXH3 instead 64-bit XXH3.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added support for cache namespaces. If a namespace configured, e.g. using
<code>CCACHE_NAMESPACE=some_string</code>, the namespace string will be added to the
hashed data for each compilation. This will make the associated cache entries
logically separate from cache entries in other namespaces, but they will still
share the same storage space. Cache entries can also be selectively removed
from the primary cache with the new command line option <code>--evict-namespace</code>,
potentially in combination with <code>--evict-older-than</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made HTTP keep-alive configurable, defaulting to off for now.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Added support for rewriting absolute path to Clang option <code>--gcc-toolchain</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_compatibility_notes_2"><a class="anchor" href="#_compatibility_notes_2"></a>Compatibility notes</h3>
<div class="ulist">
<ul>
<li>
<p>A consequence of the changed cache entry format is that ccache 4.5 will not
share cache entries with earlier versions. Different ccache versions can
however still use the same cache storage without any issues.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_11"><a class="anchor" href="#_bug_fixes_11"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a problem with special characters in the user info part of URLs for HTTP
storage.<br>
<span class="small"><em>[contributed by Russell McClellan]</em></span></p>
</li>
<li>
<p>Fixed win32 log messages about file locks.<br>
<span class="small"><em>[contributed by Luboš Luňák]</em></span></p>
</li>
<li>
<p>Fixed debug directory handling on Windows.<br>
<span class="small"><em>[contributed by Luboš Luňák]</em></span></p>
</li>
<li>
<p>The hard link and file clone features are now disabled when secondary storage
is used since they only work for the local primary cache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_4_2"><a class="anchor" href="#_ccache_4_4_2"></a>Ccache 4.4.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-09-28</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_12"><a class="anchor" href="#_bug_fixes_12"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a bug introduced in 4.4 where ccache could produce false direct cache
hits in some situations if it decides to disable the direct mode temporarily
(e.g. due to &#8220;too new header&#8221; file).<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_8"><a class="anchor" href="#_test_improvements_8"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Use shell builtin pwd command for basedir test.<br>
<span class="small"><em>[contributed by Kira Bruneau]</em></span></p>
</li>
<li>
<p>Cope with CC being a wrapper script that uses ccache.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_4_1"><a class="anchor" href="#_ccache_4_4_1"></a>Ccache 4.4.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-09-11</p>
</div>
<div class="sect2">
<h3 id="_new_features_4"><a class="anchor" href="#_new_features_4"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>The secondary storage statistics section of <code>-s/--show-stats</code> is now shown
only if it&#8217;s non-empty or with two verbose options.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added display of statistics counters for misses. Previously they were only
implicit in the &#8220;hits + misses&#8221; sums.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_13"><a class="anchor" href="#_bug_fixes_13"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed spurious crashes when using the HTTP or Redis backend and the remote
connection hung up.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made sure to always store configuration origin value.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_7"><a class="anchor" href="#_build_improvements_7"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>The matching version of lld is now used for Clang.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>The standard linker is now used if IPO (LTO) is enabled.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Disabled IPO (LTO) for MinGW toolchains since they seem to be generally
broken.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Fixed build errors with Clang on Windows.<br>
<span class="small"><em>[contributed by Orgad Shaneh]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_test_improvements_9"><a class="anchor" href="#_test_improvements_9"></a>Test improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed .incbin test with newer binutil versions.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed basedir test suite failure when using a symlinked CWD.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved output of differing text files on failure.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_4"><a class="anchor" href="#_ccache_4_4"></a>Ccache 4.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-08-19</p>
</div>
<div class="sect2">
<h3 id="_new_features_5"><a class="anchor" href="#_new_features_5"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Made it possible to share a cache over network or on a local filesystem. The
configuration option <code>secondary_storage</code>/<code>CCACHE_SECONDARY_STORAGE</code> specifies
one or several storage backends to query after the primary local cache
storage. It is also possible to configure sharding (partitioning) of the cache
to spread it over a server cluster using
<a href="https://en.wikipedia.org/wiki/Rendezvous_hashing">Rendezvous hashing</a>. See the
<em><a href="https://ccache.dev/manual/4.4.html#_secondary_storage_backends">Secondary
storage backends</a></em> chapter in the manual for details.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added an HTTP backend for secondary storage on any HTTP server that supports
GET/PUT/DELETE methods. See <a href="https://ccache.dev/howto/http-storage.html">How to
set up HTTP storage</a> for hints on how to set up an HTTP server for use with
ccache.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Added a Redis backend for secondary storage on any server that supports the
Redis protocol. See <a href="https://ccache.dev/howto/redis-storage.html">How to set up
Redis storage</a> for hints on how to set up a Redis server for use with
ccache.<br>
<span class="small"><em>[contributed by Anders F Björklund]</em></span></p>
</li>
<li>
<p>Added a filesystem backend for secondary storage. It can for instance be used
for a shared cache over networked filesystems such as NFS, or for mounting a
secondary read-only cache layer into a build container.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added <code>--trim-dir</code>, <code>--trim-max-size</code> and <code>--trim-method</code> options that can be
used to trim a secondary storage directory to a certain size, e.g. via
cron.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a configuration option <code>reshare</code>/<code>CCACHE_RESHARE</code> which makes ccache
send results to secondary storage even for primary storage cache hits.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added new statistics counters for direct/preprocessed cache misses, primary
storage hits/misses, secondary storage hits/misses/errors/timeouts and forced
recaches.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved statistics summary. The <code>-s</code>/<code>--show-stats</code> option now prints a more
condensed overview where the counters representing &#8220;uncacheable calls&#8221; are
summed as uncacheable and errors counters. The summary shows hit rate for
direct/preprocessed hits/misses, as well as primary/secondary storage
hits/misses. More details are shown with <code>-v</code>/<code>--verbose</code>. Note: Scripts
should use <code>--print-stats</code> (available since ccache 3.7) instead of trying to
parse the output of <code>--show-stats</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added a &#8220;stats log&#8221; feature (configuration option
<code>stats_log</code>/<code>CCACHE_STATSLOG</code>), which tells ccache to store statistics in a
separate log file specified by the user. It can for instance be used to
collect statistics for a single build without interference from other
concurrent builds. Statistics from the log file can then be viewed with
<code>ccache --show-log-stats</code>.<br>
<span class="small"><em>[contributed by Anders F Björklund]</em></span></p>
</li>
<li>
<p>Added support for clang&#8217;s <code>--config</code> option.<br>
<span class="small"><em>[contributed by Tom Stellard]</em></span></p>
</li>
<li>
<p>Added support for one <code>-Xarch_*</code> option that matches a corresponding <code>-arch</code>
option.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Renamed the <code>--directory</code> option to <code>--dir</code> for consistency with other
options.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made the <code>--config-path</code> and <code>--dir</code> options affect the whole command line so
that they don&#8217;t have to be put before <code>-s</code>/<code>--show-stats</code>.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made <code>--dump-manifest</code> and <code>--dump-result</code> accept filename <code>-</code> for reading
from standard input.<br>
<span class="small"><em>[contributed by Anders F Björklund]</em></span></p>
</li>
<li>
<p>Made the output of <code>--print-stats</code> sorted.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Added more internal trace points.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_14"><a class="anchor" href="#_bug_fixes_14"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a crash if using <code>base_dir</code> and <code>$PWD</code> is set to a relative path.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed a bug with <code>-fprofile-generate</code> where ccache could give false positive
cache hits when compiling with relative paths in another directory.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed a bug in <code>debug_dir</code>/<code>CCACHE_DEBUGDIR</code>. The absolute path to the object
file was not created correctly if the object file didn&#8217;t already exist.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Disabled preprocessor hits for pre-compiled headers with Clang again.<br>
<span class="small"><em>[contributed by Arne Hasselbring]</em></span></p>
</li>
<li>
<p>Fixed a problem when using the Gold linker on MIPS by only probing for a
faster linker in dev build mode and on x86_64.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Made the <code>-DENABLE_TRACING=1</code> mode work again.<br>
<span class="small"><em>[contributed by Anders F Björklund]</em></span></p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_changed_tooling_2"><a class="anchor" href="#_changed_tooling_2"></a>Changed tooling</h3>
<div class="ulist">
<ul>
<li>
<p>A C++14 compiler or newer is now required to build ccache. For GCC, this means
version 6 or newer in practice.</p>
</li>
<li>
<p>CMake 3.10 or newer is now required to build ccache.</p>
</li>
<li>
<p><a href="https://asciidoctor.org">Asciidoctor</a> is now required to build ccache
documentation.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_buildtestdocumentation_improvements"><a class="anchor" href="#_buildtestdocumentation_improvements"></a>Build/test/documentation improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed an issue in the modules test suite that showed up when running the
ccache test suite with the clang wrapper provided by Nixpkgs.<br>
<span class="small"><em>[contributed by Ryan Burns]</em></span></p>
</li>
<li>
<p>Made the nvcc_ldir test suite require a working NVCC.<br>
<span class="small"><em>[contributed by Michael Kruse]</em></span></p>
</li>
<li>
<p>Made the ivfsoverlay test suite more robust.<br>
<span class="small"><em>[contributed by Michael Kruse]</em></span></p>
</li>
<li>
<p>Fixed issue with usage of <code>/FI</code> when building ccache with MSVC.<br>
<span class="small"><em>[contributed by Michael Kruse]</em></span></p>
</li>
<li>
<p>Fixed Apple Clang detection in the integration test suite.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Made clang the default compiler when running the test suite on macOS.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Silenced stray printout from "-P -c" test case.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Fixed selection of the ccache binary to use when running the test suite with
multi-config generators like Xcode.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Fixed CMake feature detection for <code>ctim</code>/<code>mtim</code> fields in <code>struct stat</code>.<br>
<span class="small"><em>[contributed by Gregor Jasny]</em></span></p>
</li>
<li>
<p>Fixed issue with not linking to .lib correctly on Windows.<br>
<span class="small"><em>[contributed by R. Voggenauer]</em></span></p>
</li>
<li>
<p>Made it possible to override <code>CCACHE_DEV_MODE</code> on the command line.<br>
<span class="small"><em>[contributed by Joel Rosdahl]</em></span></p>
</li>
<li>
<p>Improved HTML documentation style.<br>
<span class="small"><em>[contributed by Joel Rosdahl with minor fixes by Orgad Shaneh]</em></span></p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_3"><a class="anchor" href="#_ccache_4_3"></a>Ccache 4.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-05-09</p>
</div>
<div class="sect2">
<h3 id="_new_features_6"><a class="anchor" href="#_new_features_6"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Ccache now ignores the Clang compiler option <code>-ivfsoverlay</code> and its argument
if you opt in to &#8220;ivfsoverlay sloppiness&#8221;. This is useful if you use Xcode,
which uses a virtual file system (VFS) for things like combining Objective-C
and Swift code.</p>
</li>
<li>
<p>When using <code>-P</code> in combination with <code>-E</code>, ccache now reports this as &#8220;called
for preprocessing&#8221; instead of &#8220;unsupported compiler option&#8221;.</p>
</li>
<li>
<p>Added support for <code>-specs file.specs</code> and <code>--specs file.specs</code> without an
equal sign between the arguments.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_15"><a class="anchor" href="#_bug_fixes_15"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>&#8220;Split dwarf&#8221; code paths are now disabled when outputting to <code>/dev/null</code>. This
avoids an attempt to delete <code>/dev/null.dwo</code>.</p>
</li>
<li>
<p>Made the <code>stat</code>/<code>lstat</code> wrapper function for Windows treat pending deletes as
missing files.</p>
</li>
<li>
<p>Fixed a bug that made ccache process header files redundantly for some
relative headers when using Clang.</p>
</li>
<li>
<p>The object path is now included in the input hash when using <code>-fprofile-arcs</code>
(or <code>--coverage</code>) since the object file embeds a <code>.gcda</code> path based on the
object file path.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_build_improvements_8"><a class="anchor" href="#_build_improvements_8"></a>Build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Added an <code>ENABLE_DOCUMENTATION</code> build option (default: true) that can be used
to disable the build of documentation.</p>
</li>
<li>
<p>Fixed detection of pthread features.</p>
</li>
<li>
<p>Quote CMake variables expansions to avoid errors when
<code>${CMAKE_C_FLAGS_RELWITHDEBINFO}</code> or <code>${CMAKE_CXX_FLAGS_RELWITHDEBINFO}</code>
expands to the empty string.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_2_1"><a class="anchor" href="#_ccache_4_2_1"></a>Ccache 4.2.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-03-27</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_16"><a class="anchor" href="#_bug_fixes_16"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Ccache now only duplicates the stderr file descriptor into <code>$UNCACHED_ERR_FD</code>
for calls to the preprocessor/compiler. This works around a complex bug in
interaction with GNU Make, LTO linking and the Linux PTY driver.</p>
</li>
<li>
<p>Fixed detection of color diagnostics usage when using <code>-Xclang
-fcolor-diagnostics</code> options.</p>
</li>
<li>
<p>The <code>-frecord-gcc-switches</code> compiler option is now handled correctly to avoid
false positive cache hits.</p>
</li>
<li>
<p>Made it possible for per-compilation debug log files to be written in most
argument processing error scenarios. Previously, ccache would only write debug
log files if the argument processing phase was successful.</p>
</li>
<li>
<p>Made ccache bail out on too hard Clang option <code>-gen-cdb-fragment-path</code>.</p>
</li>
<li>
<p>The <code>run_second_cpp</code> made is now enforced on macOS if <code>-g</code> is used since newer
Clang versions on macOS produce different debug information when compiling
preprocessed code.</p>
</li>
<li>
<p>Made ccache only reject <code>-f(no-)color-diagnostics</code> for a known GCC compiler.
This fixes a problem when using said option with Clang on macOS.</p>
</li>
<li>
<p>Implemented a better <code>stat</code>/<code>lstat</code> wrapper function for Windows.</p>
</li>
<li>
<p>Fixed a bug where ccache could return stale cache results on Windows.</p>
</li>
<li>
<p>Fixed handling of long command lines on Windows.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_portability_and_build_improvements"><a class="anchor" href="#_portability_and_build_improvements"></a>Portability and build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Build configuration scripts now probe for atomic increment as well. This fixes
a linking error on Sparc.</p>
</li>
<li>
<p>An existing CMake log message level is now used when warning about not finding
asciidoc.</p>
</li>
<li>
<p>Added support for building ccache with xlclang++ on AIX 7.2.</p>
</li>
<li>
<p>Fixed assertion in the &#8220;Debug option&#8221; test.</p>
</li>
<li>
<p>Made build configuration skip using ccache when building with MSVC.</p>
</li>
<li>
<p>Upgraded to doctest 2.4.6. This fixes a build error with glibc &gt;= 2.34.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation"><a class="anchor" href="#_documentation"></a>Documentation</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed markup of <code>compiler_type</code> value <code>other</code>.</p>
</li>
<li>
<p>Fixed markup of <code>debug_dir</code> documentation.</p>
</li>
<li>
<p>Fixed references to the <code>extra_files_to_hash</code> configuration option.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_2"><a class="anchor" href="#_ccache_4_2"></a>Ccache 4.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2021-02-02</p>
</div>
<div class="sect2">
<h3 id="_new_features_7"><a class="anchor" href="#_new_features_7"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Improved calculation of relative paths when using <code>base_dir</code> to also consider
canonical paths (i.e. paths with dereferenced symlinks) as candidates.</p>
</li>
<li>
<p>Added a <code>debug_dir</code> (<code>CCACHE_DEBUGDIR</code>) configuration setting for specifying a
directory for files written in debug mode.</p>
</li>
<li>
<p>Added support for compiler option <code>-x cuda</code>, understood by Clang.</p>
</li>
<li>
<p>The value of the <code>SOURCE_DATE_EPOCH</code> variable is now only hashed if it
potentially affects the output from ccache. This means that ccache now (like
before version 4.0) will be able to produce cache hits for source code that
doesn&#8217;t contain <code>__DATE__</code> or <code>__TIME__</code> macros regardless of the value of
<code>SOURCE_DATE_EPOCH</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_17"><a class="anchor" href="#_bug_fixes_17"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a bug where a non-Clang compiler would silently accept the
Clang-specific <code>-f(no-)color-diagnostics</code> option when run via ccache. This
confused feature detection made by e.g. CMake.</p>
</li>
<li>
<p>Improved creation of temporary files on Windows. Previously, ccache would in
practice reuse temporary filenames on said platform resulting in various
problems with parallel builds.</p>
</li>
<li>
<p>Fixed creation of parent directories when creating a lock file on Windows.</p>
</li>
<li>
<p>Fixed a race condition related to removal of temporary files.</p>
</li>
<li>
<p>Improved calculation of directory name for a Windows-style path.</p>
</li>
<li>
<p>A compilation result is now not stored in the cache if an included
preprocessed header file is too new. This fixes a bug where the content of a
newly created preprocessed header file could be missing from the hash,
resulting in a false positive cache hit.</p>
</li>
<li>
<p>Fixed calculation of the split DWARF filename for an object filename with zero
or multiple dots.</p>
</li>
<li>
<p>Fixed retrieval of the object file the destination is <code>/dev/null</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_portability_and_build_improvements_2"><a class="anchor" href="#_portability_and_build_improvements_2"></a>Portability and build improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Additional compiler flags like <code>-Wextra -Werror</code> are now only added when
building ccache in developer mode.</p>
</li>
<li>
<p>The developer build mode no longer enables <code>-Weverything</code> for Clang.</p>
</li>
<li>
<p><code>_XOPEN_SOURCE</code> is now defined appropriately on FreeBSD to fix missing
declaration of <code>isascii</code>.</p>
</li>
<li>
<p>Improved detection of buildability of BLAKE3 assembler files.</p>
</li>
<li>
<p>Disabled build of inode cache code on OSes without
<code>pthread_mutexattr_setpshared</code>, such as OpenBSD.</p>
</li>
<li>
<p>Made static linking the default for a Windows MinGW build.</p>
</li>
<li>
<p>Removed legacy fallback replacements of <code>mkstemp</code> and <code>realpath</code>.</p>
</li>
<li>
<p>Improved detection of SSE/AVX support.</p>
</li>
<li>
<p>Improved detection of support for the AVX2 target attribute.</p>
</li>
<li>
<p>Configuration scripts now try to detect and enable BLAKE3&#8217;s Neon support.</p>
</li>
<li>
<p>Made it possible to run the integration test suite on macOS.</p>
</li>
<li>
<p>Fixed building of 32-bit unit tests on macOS.</p>
</li>
<li>
<p>Made it possible to compile ccache for C++17.</p>
</li>
<li>
<p>Fixed printing of 64-bit <code>time_t</code> on 32-bit architectures like RISCV32.</p>
</li>
<li>
<p>Made sure to only use ASCII characters in the manual&#8217;s AsciiDoc source code to
make it possible to generate documentation in non-UTF8 locales.</p>
</li>
<li>
<p>Upgraded to optional-lite 3.4.0, fmt 7.1.3, doctest 2.4.4 and zstd 1.4.8.</p>
</li>
<li>
<p>Took steps towards being able to run the test suite on Windows.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_2"><a class="anchor" href="#_documentation_2"></a>Documentation</h3>
<div class="ulist">
<ul>
<li>
<p>Improved wording of <code>compiler_check</code> string values.</p>
</li>
<li>
<p>Improved documentation of compression levels and the <code>-X/--recompress</code> option.</p>
</li>
<li>
<p>Improved consistency of terms in the manual.</p>
</li>
<li>
<p>HTML documentation is now built and installed by default if possible.</p>
</li>
<li>
<p>Fixed incorrect documentation of configuration option <code>cache_dir</code>.</p>
</li>
<li>
<p>Added hint on how to link statically with libzstd.</p>
</li>
<li>
<p>Mention that ccache requires the <code>-c</code> compiler option.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_1"><a class="anchor" href="#_ccache_4_1"></a>Ccache 4.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-11-22</p>
</div>
<div class="sect2">
<h3 id="_new_features_8"><a class="anchor" href="#_new_features_8"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Symlinks are now followed when guessing the compiler. This makes ccache able
to guess compiler type &#8220;GCC&#8221; for a common symlink chain like this:
<code>/usr/bin/cc</code> &#8594; <code>/etc/alternatives/cc</code> &#8594; <code>/usr/bin/gcc</code> &#8594; <code>gcc-9</code> &#8594;
<code>x86_64-linux-gnu-gcc-9</code>.</p>
</li>
<li>
<p>Added a new <code>compiler_type</code> (<code>CCACHE_COMPILERTYPE</code>) configuration option that
allows for overriding the guessed compiler type.</p>
</li>
<li>
<p>Added support for caching compilations with <code>-fsyntax-only</code>.</p>
</li>
<li>
<p>Added a command line option <code>--config-path</code>, which specifies the
configuration file to operate on. It can be used instead of setting
<code>CCACHE_CONFIGPATH</code> temporarily.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_18"><a class="anchor" href="#_bug_fixes_18"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The original color diagnostics options are now retained when forcing colored
output. This fixes a bug where feature detection of the <code>-fcolor-diagnostics</code>
option would succeed when run via ccache even though the actual compiler
doesn&#8217;t support it (e.g. GCC &lt;4.9).</p>
</li>
<li>
<p>Fixed a bug related to umask when using the <code>umask</code> (<code>CCACHE_UMASK</code>)
configuration option.</p>
</li>
<li>
<p>Allow <code>ccache ccache compiler &#8230;&#8203;</code> (repeated <code>ccache</code>) again.</p>
</li>
<li>
<p>Fixed parsing of dependency file in the &#8220;depend mode&#8221; so that filenames with
space or other special characters are handled correctly.</p>
</li>
<li>
<p>Fixed rewriting of the dependency file content when the object filename
includes space or other special characters.</p>
</li>
<li>
<p>Fixed runtime detection of AVX2 support, not relying on the sometimes broken
<code>__builtin_cpu_support</code> routine.</p>
</li>
<li>
<p>Added missing parameters to a log call, thus avoiding a crash when it is
found out at runtime that file cloning is unsupported by the OS.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_portability_and_build_fixes"><a class="anchor" href="#_portability_and_build_fixes"></a>Portability and build fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The ccache binary is now linked with <code>libatomic</code> if needed. This fixes build
problems with GCC on ARM and PowerPC.</p>
</li>
<li>
<p>Fixed build of BLAKE3 code with Clang 3.4 and 3.5.</p>
</li>
<li>
<p>Fixed &#8220;use of undeclared identifier 'CLONE_NOOWNERCOPY'&#8221; build error on
macOS 10.12.</p>
</li>
<li>
<p>Fixed build problems related to missing AVX2 and AVX512 support on older
macOS versions.</p>
</li>
<li>
<p>Fixed static linkage with libgcc and libstdc++ for MinGW and made it
optional.</p>
</li>
<li>
<p>Fixed conditional compilation of &#8220;robust mutex&#8221; code for the inode cache
routines.</p>
</li>
<li>
<p>Fixed badly named man page filename (<code>Ccache.1</code> instead of <code>ccache.1</code>).</p>
</li>
<li>
<p>Disabled some tests on ancient Clang versions.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_improvements_and_fixes"><a class="anchor" href="#_other_improvements_and_fixes"></a>Other improvements and fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The man page is now built by default if the required tools are available.</p>
</li>
<li>
<p>Use CMake <code>A2X_EXE</code> variable instead of hardcoded <code>a2x</code>.</p>
</li>
<li>
<p>Improved build errors when building ccache with very old compiler versions.</p>
</li>
<li>
<p>Fall back to version &#8220;unknown&#8221; when Git is not installed.</p>
</li>
<li>
<p>Documented the relationship between <code>CCACHE_DIR</code> and <code>-d/--directory</code>.</p>
</li>
<li>
<p>Fixed incorrect reference and bad markup in the manual.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_4_0"><a class="anchor" href="#_ccache_4_0"></a>Ccache 4.0</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-10-18</p>
</div>
<div class="sect2">
<h3 id="_summary_of_major_changes"><a class="anchor" href="#_summary_of_major_changes"></a>Summary of major changes</h3>
<div class="ulist">
<ul>
<li>
<p>Changed the default cache directory location to follow the XDG base directory
specification.</p>
</li>
<li>
<p>Changed compression algorithm from Deflate (zlib) to Zstandard, enabled by
default.</p>
</li>
<li>
<p>Added functionality for recompressing cache content with a higher compression
level.</p>
</li>
<li>
<p>Changed hash algorithm from MD4 to BLAKE3.</p>
</li>
<li>
<p>Added checksumming with XXH3 to detect data corruption.</p>
</li>
<li>
<p>Improved cache directory structure.</p>
</li>
<li>
<p>Added support for using file cloning (AKA &#8220;reflinks&#8221;).</p>
</li>
<li>
<p>Added an experimental &#8220;inode cache&#8221; for file hashes.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_compatibility_notes_3"><a class="anchor" href="#_compatibility_notes_3"></a>Compatibility notes</h3>
<div class="ulist">
<ul>
<li>
<p>The default location of the cache directory has changed to follow the XDG
base directory specification (<a href="#_detailed_functional_changes">more details
below</a>). This means that scripts can no longer assume that the cache
directory is <code>~/.ccache</code> by default. The <code>CCACHE_DIR</code> environment variable
still overrides the default location just like before.</p>
</li>
<li>
<p>The cache directory structure has changed compared to previous versions
(<a href="#_detailed_functional_changes">more details below</a>). This means that ccache
4.0 will not share cache results with earlier versions. It is however safe to
run ccache 4.0 and earlier versions against the same cache directory: cache
bookkeeping, statistics and cleanup are backward compatible, with the minor
exception that some statistics counters incremented by ccache 4.0 won&#8217;t be
visible when running <code>ccache -s</code> with an older version.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_changed_tooling_3"><a class="anchor" href="#_changed_tooling_3"></a>Changed tooling</h3>
<div class="ulist">
<ul>
<li>
<p>CMake is now used instead of Autoconf for configuration and building.</p>
</li>
<li>
<p>A C++11 compiler, a C99 compiler and CMake 3.4.3 or newer are now required to
build ccache.</p>
</li>
<li>
<p>Ccache can now be built using Microsoft Visual C++.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_detailed_functional_changes"><a class="anchor" href="#_detailed_functional_changes"></a>Detailed functional changes</h3>
<div class="ulist">
<ul>
<li>
<p>All data of a cached result is now stored in a single file called &#8220;result&#8221;
instead of up to seven files. This reduces inode usage and improves data
locality.</p>
</li>
<li>
<p>Added compression of result and manifest files using the
<a href="http://zstd.net">Zstandard</a> algorithm. Compression is enabled by default with
compression level 1. This makes ccache able to store more data in the cache.
Previously compression using Deflate (zlib) was available but disabled by
default. Files can be recompressed with another compression level later with
the <code>-X/--recompress</code> option described further below.</p>
</li>
<li>
<p>Changed from MD4 to <a href="https://blake3.io">BLAKE3</a> for hashing input. This
improves performance and reduces the risk of hash collisions.</p>
</li>
<li>
<p>Added checksumming of result and manifest files using the
<a href="http://xxhash.com">XXH3</a> algorithm to detect data corruption.</p>
</li>
<li>
<p>Ccache now follows the
<a href="https://specifications.freedesktop.org/basedir-spec/">XDG base directory
specification</a>. This means that the default cache directory on Unix systems
is <code>$XDG_CACHE_HOME/ccache</code> (with <code>~/.cache/ccache</code> as the fallback if
<code>XDG_CACHE_HOME</code> is not set) and the configuration file is
<code>$XDG_CONFIG_HOME/ccache/ccache.conf</code> (with <code>~/.config/ccache/ccache.conf</code> as
the fallback). On macOS, the fallbacks are <code>~/Library/Caches/ccache</code> and
<code>~/Library/Preferences/ccache/ccache.conf</code>. On Windows, the fallbacks are
<code>%APPDATA%/ccache</code> and <code>%APPDATA%/ccache/ccache.conf</code>. Exception: If the
legacy <code>~/.ccache</code> directory exists, that directory is used as the default
cache location and the configuration file is <code>~/.ccache/ccache.conf</code>.</p>
</li>
<li>
<p>Cache statistics are now stored in files on cache level 2 to reduce lock
contention when there are many parallel compilations.</p>
</li>
<li>
<p>An appropriate cache directory level structure is now chosen automatically.
The <code>cache_dir_levels</code> (<code>CCACHE_NLEVELS</code>) configuration option has therefore
been removed.</p>
</li>
<li>
<p>Added an experimental &#8220;inode cache&#8221; for file hashes, allowing computed hash
values to be reused both within and between builds. The inode cache is off by
default but can be enabled by setting <code>inode_cache</code> (<code>CCACHE_INODECACHE</code>) to
<code>true</code>.</p>
</li>
<li>
<p>Added support for using file cloning (AKA &#8220;reflinks&#8221;) on Btrfs, XFS and APFS
to copy data to and from the cache very efficiently.</p>
</li>
<li>
<p>Two measures have been implemented to make the hard link mode safer:
hard-linked files are made read-only and inadvertent content changes that
affect file size are detected.</p>
</li>
<li>
<p>Added a command line option <code>-x/--show-compression</code> which shows statistics
about cache compression.</p>
</li>
<li>
<p>Added a command line option <code>-X/--recompress</code> which recompresses the cache
data with another compression level or makes it uncompressed. If you choose
to disable compression by default, or choose to use a compression level with
a low compression ratio, you can recompress the cache with a higher
compression level after the build or at another time when there are more CPU
cycles available, for instance every night. Only files that are currently
compressed with a different level than the wanted level will be recompressed.</p>
</li>
<li>
<p>Added a command line option <code>--evict-older-than</code> which removes cache entries
older than a certain age.</p>
</li>
<li>
<p>Added a command line option <code>-d/--directory</code> which specifies a cache
directory to operate on. It can be used instead of setting <code>CCACHE_DIR</code>
temporarily.</p>
</li>
<li>
<p>A progress bar has been added to show the progress of time-consuming options
like <code>-c/--cleanup</code>, <code>-C/--clear</code>, <code>--evict-older-than</code>,
<code>-x/--show-compression</code> and <code>-X/--recompress</code>.</p>
</li>
<li>
<p>When supported by the CPU, a SIMD-friendly (using AVX2) algorithm is now used
to scan input source code for <code>__DATE__</code>, <code>__TIME__</code> and <code>__TIMESTAMP__</code>
macros. This can decrease the number of CPU cycles for a direct cache hit with
up to 15% in some cases.</p>
</li>
<li>
<p>Some unnecessary <code>stat(2)</code> system calls are now avoided when verifying header
files.</p>
</li>
<li>
<p>Compiler diagnostic messages are now always cached in color. Ccache then
strips the color codes on the fly when requested explicitly by a command line
option or when stderr does not refer to a TTY. This allows IDEs and terminals
to share cached compilation results.</p>
</li>
<li>
<p>The configuration option <code>compiler</code> (<code>CCACHE_COMPILER</code>) now always takes
effect if specified. Previously, the configuration option was only used when
the compiler specified on the command line was looked up via <code>PATH</code> (i.e.,
not when an absolute path was specified).</p>
</li>
<li>
<p>Added optional logging to syslog if <code>log_file</code> (<code>CCACHE_LOGFILE</code>) is set to
<code>syslog</code>.</p>
</li>
<li>
<p>The compiler option <code>-fmodules</code> is now handled in the &#8220;depend mode&#8221;. If
&#8220;depend mode&#8221; is disabled the option is still considered too hard and ccache
will fall back to running the compiler.</p>
</li>
<li>
<p>Ccache can now cache compilations with coverage notes (<code>.gcno</code> files)
produced by GCC 9+ in combination with <code>-fprofile-dir=dir</code>.</p>
</li>
<li>
<p><code>realpath(3)</code> is no longer used for normalization when computing relative
paths. This makes it possible to get cache hits when the source or build
directory is a symbolic link to an absolute path that includes unstable
information like build IDs or timestamps.</p>
</li>
<li>
<p>Added an <code>ignore_options</code> (<code>CCACHE_IGNOREOPTIONS</code>) configuration option which
makes it possible to exclude compiler options from the hash.</p>
</li>
<li>
<p>Added an <code>absolute_paths_in_stderr</code> (<code>CCACHE_ABSSTDERR</code>) configuration option
which makes ccache rewrite absolute paths in compiler warnings and errors to
relative.</p>
</li>
<li>
<p>Improved handling of umask. The configured <code>umask</code> (<code>CCACHE_UMASK</code>) is now
only applied to files and directories in the cache directory. Previously the
umask was applied to all files produced by ccache and the executed compiler.</p>
</li>
<li>
<p>Ccache is now able to share cache entries for different object file names
when using <code>-MD</code> or <code>-MMD</code>.</p>
</li>
<li>
<p>Clang&#8217;s <code>-Xclang</code> (used by CMake for precompiled headers),
<code>-fno-pch-timestamp</code>, <code>-emit-pch</code>, <code>-emit-pth</code> and <code>-include-pth</code> options are
now understood.</p>
</li>
<li>
<p>Added support for the HIP (&#8220;C++ Heterogeneous-Compute Interface for
Portability&#8221;) language.</p>
</li>
<li>
<p>The manifest format now allows for header files larger than 4 GiB.</p>
</li>
<li>
<p>Made it possible to once again cache compilations with <code>__DATE__</code> in the
source code.</p>
</li>
<li>
<p>Added handling of the <code>__TIMESTAMP__</code> macro.</p>
</li>
<li>
<p>An absolute input source path is now rewritten to a relative path when using
<code>base_dir</code>.</p>
</li>
<li>
<p><code>waitpid</code> system calls interrupted by a signal are now handled correctly.</p>
</li>
<li>
<p>Made handling of <code>.dwo</code> files and interaction between <code>-gsplit-dwarf</code> and
other <code>-g*</code> options more robust.</p>
</li>
<li>
<p>The &#8220;couldn&#8217;t find compiler&#8221; statistics counter is no longer incremented
when ccache exits with a fatal error.</p>
</li>
<li>
<p>Failure to run a <code>compiler_check</code> command is no longer a fatal error.</p>
</li>
<li>
<p>Added command line options <code>--dump-result</code> and <code>--extract-result</code> for
inspecting and extracting result files.</p>
</li>
<li>
<p>Added a command line option <code>--checksum-file</code> for debugging or evaluating the
checksum algorithm.</p>
</li>
<li>
<p>Improved error message for <code>ccache -o=K=V</code> (trying to set a configuration
option named <code>=K</code>).</p>
</li>
<li>
<p>Made timestamps in statistics files Y2038-proof.</p>
</li>
<li>
<p>Removed code for populating a newly created configuration file with max cache
size and max files values for cache directories created by ccache versions
older than 3.2 (released 2014).</p>
</li>
<li>
<p>Removed knowledge about a top-level <code>stats</code> file created by ccache versions
older than 3.1 (released 2010).</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_improvements"><a class="anchor" href="#_other_improvements"></a>Other improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Improved help text and documentation of command line options.</p>
</li>
<li>
<p>Improved documentation of the <code>base_dir</code> configuration option.</p>
</li>
<li>
<p>Improved documentation of preprocessor and direct modes.</p>
</li>
<li>
<p>Added HTML anchors to configuration options in the manual so that it is
possible link to a specific option.</p>
</li>
<li>
<p>Tweaked placement of &#8220;(readonly)&#8221; in output of <code>ccache -s</code>.</p>
</li>
<li>
<p>Improved visibility of color output from the test suite.</p>
</li>
<li>
<p>Fixed a problem when running the test suite with Clang without a libgcov
library available.</p>
</li>
<li>
<p>Fixed test suite problems on macOS.</p>
</li>
<li>
<p>Disabled hardlink tests on AFS since it lacks such support.</p>
</li>
<li>
<p>Disabled read-only tests on file systems that lack such support.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_12"><a class="anchor" href="#_ccache_3_7_12"></a>Ccache 3.7.12</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-10-01</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_19"><a class="anchor" href="#_bug_fixes_19"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Coverage files (<code>.gcno</code>) produced by GCC 9+ when using <code>-fprofile-dir=dir</code>
are now handled gracefully by falling back to running the compiler.</p>
</li>
<li>
<p>Fixed writing to log file larger than 2 GiB when running ccache compiled in
32-bit mode.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other"><a class="anchor" href="#_other"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Improved documentation about sharing a cache on NFS.</p>
</li>
<li>
<p>Fixed test case failures with old objdump versions.</p>
</li>
<li>
<p>Fixed test case failures with GCC 4.4.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_11"><a class="anchor" href="#_ccache_3_7_11"></a>Ccache 3.7.11</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-07-21</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_20"><a class="anchor" href="#_bug_fixes_20"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Added knowledge about <code>-fprofile-{correction,reorder-functions,values}</code>.</p>
</li>
<li>
<p>ccache now handles the Intel compiler option <code>-xCODE</code> (where <code>CODE</code> is a
processor feature code) correctly.</p>
</li>
<li>
<p>Added support for NVCC&#8217;s <code>-Werror</code> and <code>--Werror</code> options.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_2"><a class="anchor" href="#_other_2"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>ccache&#8217;s &#8220;Directory is not hashed if using -gz[=zlib]&#8221; tests are now skipped
for GCC 6.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_10"><a class="anchor" href="#_ccache_3_7_10"></a>Ccache 3.7.10</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-06-22</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_21"><a class="anchor" href="#_bug_fixes_21"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Improved handling of profiling options. ccache should now work correctly for
profiling options like <code>-fprofile-{generate,use}[=path]</code> for GCC ≥ 9 and
Clang as well as <code>-fauto-profile[=path]</code> and the Clang-specific
<code>-fprofile-instr-{generate,use}[=path]</code> and <code>-fprofile-sample-{use,accurate}</code>
options.</p>
</li>
<li>
<p>ccache now copies files directly from the cache to the destination file
instead of via a temporary file. This avoids problems when using filenames
long enough to be near the file system&#8217;s filename max limit.</p>
</li>
<li>
<p>When the hard-link mode is enabled, ccache now only uses hard links for
object files, not other files like dependency files. This is because
compilers unlink object files before writing to them but they don&#8217;t do that
for dependency files, so the latter can become overwritten and therefore
corrupted in the cache.</p>
</li>
<li>
<p>Fixed a glitch related to hard-link mode and an empty cache.</p>
</li>
<li>
<p>ccache now supports the ccache.conf file to be a symlink.</p>
</li>
<li>
<p>Temporary files are now deleted immediately on signals like SIGTERM and
SIGINT instead of some time later in a cleanup phase.</p>
</li>
<li>
<p>Fixed a bug that affected ccache&#8217;s <code>-o/--set-config</code> option for the
<code>base_dir</code> and <code>cache_dir_levels</code> keys.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_9"><a class="anchor" href="#_ccache_3_7_9"></a>Ccache 3.7.9</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-03-29</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_22"><a class="anchor" href="#_bug_fixes_22"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed replacing of /dev/null when building as root with hard link mode
enabled and using <code>-o /dev/null</code>.</p>
</li>
<li>
<p>Removed incorrect assertion resulting in &#8220;ccache: error: Internal error in
format&#8221; when using <code>-fdebug-prefix-map=X=</code> with X equal to <code>$PWD</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_3"><a class="anchor" href="#_other_3"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Improved CUDA/NVCC support: Recognize <code>-dc</code> and <code>-x cu</code> options.</p>
</li>
<li>
<p>Improved name of temporary file used in NFS-safe unlink.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_8"><a class="anchor" href="#_ccache_3_7_8"></a>Ccache 3.7.8</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-03-16</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_23"><a class="anchor" href="#_bug_fixes_23"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Use <code>$PWD</code> instead of the real CWD (current working directory) when checking
for CWD in preprocessed output. This fixes a problem when <code>$PWD</code> includes a
symlink part and the user has set <code>hash_dir = false</code>.</p>
</li>
<li>
<p>Rewrote the Windows version of the lockfile routines. This should mitigate
several problems with the old implementation.</p>
</li>
<li>
<p>If <code>localtime_r</code> fails the epoch time is now logged instead of garbage.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_4"><a class="anchor" href="#_other_4"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Improved error message when a boolean environment variable has an invalid
value.</p>
</li>
<li>
<p>Improved the regression fix in ccache 3.7.5 related to not passing
compilation-only options to the preprocessor.</p>
</li>
<li>
<p>ccache&#8217;s PCH test suite now skips running the tests if it detects broken PCH
compiler support.</p>
</li>
<li>
<p>Fixed unit test failure on Windows.</p>
</li>
<li>
<p>Fixed &#8220;stringop-truncation&#8221; build warning on Windows.</p>
</li>
<li>
<p>Improved &#8220;x_rename&#8221; implementation on Windows.</p>
</li>
<li>
<p>Improved removal of temporary file when rewriting absolute paths to relative
in the dependency file.</p>
</li>
<li>
<p>Clarified &#8220;include_file_ctime sloppiness&#8221; in the Performance section in the
manual.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_7"><a class="anchor" href="#_ccache_3_7_7"></a>Ccache 3.7.7</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2020-01-05</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_24"><a class="anchor" href="#_bug_fixes_24"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a bug related to object file location in the dependency file (if using
<code>-MD</code> or <code>-MMD</code> but not <code>-MF</code> and the build directory is not the same as the
source directory then the object file location in the <code>.d</code> file would become
incorrect). This fixes regression in ccache 3.7.5 introduced by the bug fix
related to EDG-based compilers. Note that this removes support for EDG-based
compilers again. (A better fix for this is planned for ccache 4.0.)</p>
</li>
<li>
<p>Removed the unify mode since it has bugs and shortcomings that are non-trivial
or impossible to fix: it doesn&#8217;t work with the direct mode, it doesn&#8217;t handle
C++ raw strings correctly, it can give false cache hits for <code>.incbin</code>
directives, it&#8217;s turned off when using <code>-g</code> and it can make line numbers in
warning messages and <code><em>LINE</em></code> macros incorrect.</p>
</li>
<li>
<p>mtime and ctime values are now stored in the manifest files only when
sloppy_file_stat is set. This avoids adding superfluous manifest file entries
on direct mode cache misses.</p>
</li>
<li>
<p>A &#8220;Result:&#8221; line is now always printed to the log.</p>
</li>
<li>
<p>The &#8220;cache miss&#8221; statistics counter will now be updated for read-only cache
misses, making it consistent with the cache hit case.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_6"><a class="anchor" href="#_ccache_3_7_6"></a>Ccache 3.7.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-11-17</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_25"><a class="anchor" href="#_bug_fixes_25"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The opt-in &#8220;file_macro sloppiness&#8221; mode has been removed so that the input
file path now is always included in the direct mode hash. This fixes a bug
that could result in false cache hits in an edge case when &#8220;file_macro
sloppiness&#8221; is enabled and several identical source files include a relative
header file with the same name but in different directories.</p>
</li>
<li>
<p>Statistics files are no longer lost when the filesystem of the cache is full.</p>
</li>
<li>
<p>Bail out on too hard Clang option <code>-MJarg</code> (in addition to the previous
bailout of <code>-MJ arg</code>).</p>
</li>
<li>
<p>Properly handle color diagnostics in the depend mode as well.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_5"><a class="anchor" href="#_ccache_3_7_5"></a>Ccache 3.7.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-10-22</p>
</div>
<div class="sect2">
<h3 id="_new_features_9"><a class="anchor" href="#_new_features_9"></a>New features</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for <code>-MF=arg</code> (with an extra equal sign) as understood by
EDG-based compilers.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_26"><a class="anchor" href="#_bug_fixes_26"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression in 3.7.2 that could result in a warning message instead of
an error in an edge case related to usage of &#8220;-Werror&#8221;.</p>
</li>
<li>
<p>An implicit <code>-MQ</code> is now passed to the preprocessor only if the object file
extension is non-standard. This will make it easier to use EDG-based
compilers (e.g. GHS) which don&#8217;t understand <code>-MQ</code>. (This is a bug fix of the
corresponding improvement implemented in ccache 3.4.)</p>
</li>
<li>
<p>ccache now falls back to running the real compiler instead of failing fataly
if an internal temporary file is missing after compilation.</p>
</li>
<li>
<p>Fixed a crash if localtime returns null pointer in localtime_r replacement.</p>
</li>
<li>
<p>Fixed header file dependency tracking when building ccache itself.</p>
</li>
<li>
<p>Fixed warning during configure in out-of-tree build in developer mode.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_4"><a class="anchor" href="#_ccache_3_7_4"></a>Ccache 3.7.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-09-12</p>
</div>
<div class="sect2">
<h3 id="_improvements"><a class="anchor" href="#_improvements"></a>Improvements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for the <code>-gz[=type]</code> compiler option (previously ccache would
think that &#8220;-gz&#8221; alone would enable debug information, thus potentially
including the current directory in the hash).</p>
</li>
<li>
<p>Added support for converting paths like &#8220;/c/users/&#8230;&#8203;&#8221; into relative paths
on Windows.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_3"><a class="anchor" href="#_ccache_3_7_3"></a>Ccache 3.7.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-08-17</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_27"><a class="anchor" href="#_bug_fixes_27"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The cache size (which is counted in &#8220;used disk blocks&#8221;) is now correct on
filesystems that use more or less disk blocks than conventional filesystems,
e.g. ecryptfs or btrfs/zfs with transparent compression. This also fixes a
related problem with ccache&#8217;s own test suite when run on such file systems.</p>
</li>
<li>
<p>Fixed a regression in 3.7.2 when using the compiler option &#8220;-Werror&#8221; and
then &#8220;-Wno-error&#8221; later on the command line.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_2"><a class="anchor" href="#_ccache_3_7_2"></a>Ccache 3.7.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-07-19</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_28"><a class="anchor" href="#_bug_fixes_28"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The compiler option <code>-gdwarf*</code> no longer forces &#8220;run_second_cpp = true&#8221;.</p>
</li>
<li>
<p>Added verification that the value passed to the <code>-o/--set-config</code> option is
valid.</p>
</li>
<li>
<p>Fixed detection of precompiled headers in the depend mode.</p>
</li>
<li>
<p>Bail out on too hard Clang option <code>-ftime-trace</code>.</p>
</li>
<li>
<p>ccache now updates the correct stats file when adding/updating manifest
files. This bug previously made the file and size statistics counters
incorrect over time.</p>
</li>
<li>
<p>Fixed warnings from Clang about unused arguments during preprocessing.</p>
</li>
<li>
<p>Unknown manifest versions are now handled gracefully in <code>--dump-manifest</code>.</p>
</li>
<li>
<p>Fixed <code>make check</code> with &#8220;funny&#8221; locales.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_documentation_3"><a class="anchor" href="#_documentation_3"></a>Documentation</h3>
<div class="ulist">
<ul>
<li>
<p>Added a hint about not running <code>autogen.sh</code> when building from a release
archive.</p>
</li>
<li>
<p>Mention that <code>xsltproc</code> is needed when building from the source repository.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7_1"><a class="anchor" href="#_ccache_3_7_1"></a>Ccache 3.7.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-05-01</p>
</div>
<div class="sect2">
<h3 id="_changes"><a class="anchor" href="#_changes"></a>Changes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a problem when using the compiler option <code>-MF /dev/null</code>.</p>
</li>
<li>
<p>Long commandlines are now handled gracefully on Windows by using the <code>@file</code>
syntax to avoid hitting the commandline size limit.</p>
</li>
<li>
<p>Fixed complaint from GCC 9&#8217;s <code>-Werror=format-overflow</code> when compiling ccache
itself.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_7"><a class="anchor" href="#_ccache_3_7"></a>Ccache 3.7</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-04-23</p>
</div>
<div class="sect2">
<h3 id="_changes_2"><a class="anchor" href="#_changes_2"></a>Changes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed crash when the debug mode is enabled and the output file is in a
non-writable directory, e.g. when the output file is <code>/dev/null</code>.</p>
</li>
<li>
<p>Fixed an issue when printing very large log messages to the debug log.</p>
</li>
<li>
<p>Fixed bugs related to support for <code>-gsplit-dwarf</code>. Previously ccache could
produce an incorrect link to the <code>.dwo</code> file in the <code>.o</code> file.</p>
</li>
<li>
<p>Compilations with /dev/null as the input file are now cached.</p>
</li>
<li>
<p>ccache has learned how to construct the object filename if no <code>-o</code> option is
given and the source filename does not include a <code>.</code> or ends with a <code>.</code>.</p>
</li>
<li>
<p>Fixed a temporary file leak when the depend mode is enabled and the compiler
produces standard error output.</p>
</li>
<li>
<p>Fixed a bug in the depend mode where a manifest hash only could be associated
with one set of header dependencies.</p>
</li>
<li>
<p>Manifest files did not get marked as used on direct cache hits, so the LRU
cache cleanup would incorrectly remove them eventually. This has been fixed.</p>
</li>
<li>
<p>The rewriting of absolute paths into relative paths in the dependency file
has been enabled in the depend mode as well.</p>
</li>
<li>
<p>ccache now ignores unknown keys in configuration files for forward
compatibility.</p>
</li>
<li>
<p>Rearranged command-line options into sections in the help text.</p>
</li>
<li>
<p>Documented the previously undocumented <code>--dump-manifest</code> and <code>--hash-file</code>
options (only useful for debugging ccache itself).</p>
</li>
<li>
<p>Added missing documentation for the command-line option <code>-k/--get-config</code>
added in ccache 3.5.</p>
</li>
<li>
<p>Renamed the <code>--print-config</code> command to <code>--show-config</code>.</p>
</li>
<li>
<p>Added a new <code>--print-stats</code> command that prints statistics counters in
machine-parsable (tab-separated) format.</p>
</li>
<li>
<p>ccache no longer creates a missing output directory, thus mimicking the
compiler behavior for <code>-o out/obj.o</code> when <code>out</code> doesn&#8217;t exist.</p>
</li>
<li>
<p><code>-fdebug-prefix-map=ARG</code>, <code>-ffile-prefix-map=ARG</code> and <code>-fmacro-prefix-map=ARG</code>
are now included in the hash, but only the part before &#8220;ARG&#8221;. This fixes a
bug where compiler feature detection of said flags would not work correctly
with ccache.</p>
</li>
<li>
<p>Bail out on too hard compiler option <code>-gtoggle</code>.</p>
</li>
<li>
<p>Bail out on too hard Clang options <code>--analyze</code> and <code>-analyze</code>.</p>
</li>
<li>
<p>Improved debug logging of file hashes in depend mode.</p>
</li>
<li>
<p>Improved handling of various <code>-g*</code> options. In particular, ccache now
understands that <code>-g0</code> cancels out previous <code>-g* options</code>.</p>
</li>
<li>
<p>Worked around a problem with Automake related to <code>.d</code> files when using the
hard link mode.</p>
</li>
<li>
<p>Added opt-in (at configure time) support for enabling trace logs for
profiling ccache itself. See <code>doc/DEVELOPER.md</code> in the code tree for more
information</p>
</li>
<li>
<p>Removed support for Fortran 77 again. Some Fortran support was added in
ccache 3.3, but the implementation did not work when Fortran modules are
involved.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_6"><a class="anchor" href="#_ccache_3_6"></a>Ccache 3.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-01-14</p>
</div>
<div class="sect2">
<h3 id="_changes_3"><a class="anchor" href="#_changes_3"></a>Changes</h3>
<div class="ulist">
<ul>
<li>
<p>ccache now has an opt-in &#8220;depend mode&#8221;. When enabled, ccache never executes
the preprocessor, which results in much lower cache miss overhead at the
expense of a lower potential cache hit rate. The depend mode is only possible
to use when the compiler option <code>-MD</code> or <code>-MMD</code> is used.</p>
</li>
<li>
<p>Added support for GCC&#8217;s <code>-ffile-prefix-map</code> option. The <code>-fmacro-prefix-map</code>
option is now also skipped from the hash.</p>
</li>
<li>
<p>Added support for multiple <code>-fsanitize-blacklist</code> arguments.</p>
</li>
<li>
<p>ccache now includes the environment variables <code>LANG</code>, <code>LC_ALL</code>, <code>LC_CTYPE</code>
and <code>LC_MESSAGES</code> in the hash since they may affect localization of compiler
warning messages. Set sloppiness to <code>locale</code> to opt out of this.</p>
</li>
<li>
<p>Fixed a problem due to Clang overwriting the output file when compiling an
assembler file.</p>
</li>
<li>
<p>Clarified the manual to explain the reasoning behind the &#8220;file_macro&#8221;
sloppiness setting in a better way.</p>
</li>
<li>
<p>ccache now handles several levels of nonexistent directories when rewriting
absolute paths to relative.</p>
</li>
<li>
<p>A new sloppiness setting <code>clang_index_store</code> makes ccache skip the Clang
compiler option <code>-index-store-path</code> and its argument when computing the
manifest hash. This is useful if you use Xcode, which uses an index store
path derived from the local project path. Note that the index store won&#8217;t be
updated correctly on cache hits if you enable this option.</p>
</li>
<li>
<p>Rename sloppiness <code>no_system_headers</code> to <code>system_headers</code> for consistency
with other options. <code>no_system_headers</code> can still be used as an
(undocumented) alias.</p>
</li>
<li>
<p>The GCC variables &#8220;DEPENDENCIES_OUTPUT&#8221; and &#8220;SUNPRO_DEPENDENCIES&#8221; are now
supported correctly.</p>
</li>
<li>
<p>The algorithm that scans for <code><em>_DATE</em></code> and <code>__TIME__</code> tokens in the hashed
source code now doesn&#8217;t produce false positives for tokens where <code>__DATE__</code>
or <code>__TIME__</code> is a substring.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_5_1"><a class="anchor" href="#_ccache_3_5_1"></a>Ccache 3.5.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2019-01-02</p>
</div>
<div class="sect2">
<h3 id="_changes_4"><a class="anchor" href="#_changes_4"></a>Changes</h3>
<div class="ulist">
<ul>
<li>
<p>Added missing getopt_long.c source file to release archive.</p>
</li>
<li>
<p>Fixed (harmless) compiler warnings when building ccache object files.</p>
</li>
<li>
<p>CFLAGS is no longer passed to the linker when linking ccache.</p>
</li>
<li>
<p>Improved development mode build flags.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_5"><a class="anchor" href="#_ccache_3_5"></a>Ccache 3.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-10-15</p>
</div>
<div class="sect2">
<h3 id="_changes_5"><a class="anchor" href="#_changes_5"></a>Changes</h3>
<div class="ulist">
<ul>
<li>
<p>Added a boolean <code>debug</code> (<code>CCACHE_DEBUG</code>) configuration option. When enabled,
ccache will create per-object debug files that are helpful e.g. when debugging
unexpected cache misses. See also the new &#8220;Cache debugging&#8221; section in the
manual.</p>
</li>
<li>
<p>Renamed <code>CCACHE_CC</code> to <code>CCACHE_COMPILER</code> (keeping the former as a deprecated
alias).</p>
</li>
<li>
<p>Added a new command-line option <code>-k/--get-config</code> that prints the value of a
config key.</p>
</li>
<li>
<p>It is now possible to let ccache hash a precomputed checksum file instead of
the full content of a precompiled header. This can save time for large
precompiled headers. Note that the build system needs to keep the checksum
file in sync with the precompiled header for this to work.</p>
</li>
<li>
<p>Improved performance substantially when using <code>hash_dir = false</code> on platforms
like macOS where <code>getcwd()</code> is slow.</p>
</li>
<li>
<p>Added &#8220;stats updated&#8221; timestamp in <code>ccache -s</code> output. This can be useful if
you wonder whether ccache actually was used for your last build.</p>
</li>
<li>
<p>Renamed &#8220;stats zero time&#8221; to &#8220;stats zeroed&#8221; and documented it. The counter
is also now only present in <code>ccache -s</code> output when <code>ccache -z</code> actually has
been called.</p>
</li>
<li>
<p>The content of the <code>-fsanitize-blacklist</code> file is now included in the hash,
so updates to the file will now correctly result in separate cache entries.</p>
</li>
<li>
<p>It&#8217;s now possible to opt out of building and installing man pages when
running <code>make install</code> in the source repository.</p>
</li>
<li>
<p>If the compiler type can&#8217;t be detected (e.g. if it is named <code>cc</code>), use safer
defaults that won&#8217;t trip up Clang.</p>
</li>
<li>
<p>Made the ccache test suite work on FreeBSD.</p>
</li>
<li>
<p>Added <code>file_stat_matches_ctime</code> option to disable ctime check if
<code>file_stat_matches</code> is enabled.</p>
</li>
<li>
<p>Made &#8220;./configure --without-bundled-zlib&#8221; do what&#8217;s intended.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_4_3"><a class="anchor" href="#_ccache_3_4_3"></a>Ccache 3.4.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-09-02</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_29"><a class="anchor" href="#_bug_fixes_29"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a race condition when creating the initial config file in the cache
directory.</p>
</li>
<li>
<p>Bail out on too hard Clang option <code>-MJ</code>.</p>
</li>
<li>
<p>Bail out on too hard option <code>-save-temps=obj</code>.</p>
</li>
<li>
<p>Handle separate parameter to Clang option <code>-target</code> correctly.</p>
</li>
<li>
<p>Upgraded bundled zlib to version 1.2.11.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_4_2"><a class="anchor" href="#_ccache_3_4_2"></a>Ccache 3.4.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-03-25</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_30"><a class="anchor" href="#_bug_fixes_30"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The cleanup algorithm has been fixed to not misbehave when files are removed
by another process while the cleanup process is running. Previously, too many
files could be removed from the cache if multiple cleanup processes were
triggered at the same time, in extreme cases trimming the cache to a much
smaller size than the configured limits.</p>
</li>
<li>
<p>Correctly hash preprocessed headers located in a &#8220;.gch directory&#8221;.
Previously, ccache would not pick up changes to such precompiled headers,
risking false positive cache hits.</p>
</li>
<li>
<p>Fixed build failure when using the bundled zlib sources.</p>
</li>
<li>
<p>ccache 3.3.5 added a workaround for not triggering Clang errors when a
precompiled header&#8217;s dependency has an updated timestamp (but identical
content). That workaround is now only applied when the compiler is Clang.</p>
</li>
<li>
<p>Made it possible to perform out-of-source builds in dev mode again.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_4_1"><a class="anchor" href="#_ccache_3_4_1"></a>Ccache 3.4.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-02-11</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_31"><a class="anchor" href="#_bug_fixes_31"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed printing of version number in <code>ccache --version</code>.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_4"><a class="anchor" href="#_ccache_3_4"></a>Ccache 3.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-02-11</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements"><a class="anchor" href="#_new_features_and_enhancements"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>The compiler option form <code>--sysroot arg</code> is now handled like the documented
<code>--sysroot=arg</code> form.</p>
</li>
<li>
<p>Added support for caching <code>.su</code> files generated by GCC flag <code>-fstack-usage</code>.</p>
</li>
<li>
<p>ccache should now work with distcc&#8217;s &#8220;pump&#8221; wrapper.</p>
</li>
<li>
<p>The optional unifier is no longer disabled when the direct mode is enabled.</p>
</li>
<li>
<p>Added support for NVCC compiler options <code>--compiler-bindir/-ccbin</code>,
<code>--output-directory/-odir</code> and <code>--libdevice-directory/-ldir</code>.</p>
</li>
<li>
<p>Boolean environment variable settings no longer accept the following
(case-insensitive) values: <code>0</code>, <code>false</code>, <code>disable</code> and <code>no</code>. All other values
are accepted and taken to mean &#8220;true&#8221;. This is to stop users from setting
e.g. <code>CCACHE_DISABLE=0</code> and then expect the cache to be used.</p>
</li>
<li>
<p>Improved support for <code>run_second_cpp = false</code>: If combined with passing
<code>-fdirectives-only</code> (GCC) or <code>frewrite-includes</code> (Clang) to the compiler,
diagnostics warnings and similar will be correct.</p>
</li>
<li>
<p>An implicit <code>-MQ</code> is now passed to the preprocessor only if the object file
extension is non-standard. This should make it easier to use EDG-based
compilers (e.g. GHS) which don&#8217;t understand <code>-MQ</code>.</p>
</li>
<li>
<p>ccache now treats an unreadable configuration file just like a missing
configuration file.</p>
</li>
<li>
<p>Documented more pitfalls with enabling <code>hard_links</code> (<code>CCACHE_HARDLINK</code>).</p>
</li>
<li>
<p>Documented caveats related to colored warnings from compilers.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_32"><a class="anchor" href="#_bug_fixes_32"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>File size and number counters are now updated correctly when files are
overwritten in the cache, e.g. when using <code>CCACHE_RECACHE</code>.</p>
</li>
<li>
<p><code>run_second_cpp</code> is now forced for NVCC.</p>
</li>
<li>
<p>Fixed how the NVCC options <code>-optf</code> and <code>-odir</code> are handled.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_6"><a class="anchor" href="#_ccache_3_3_6"></a>Ccache 3.3.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-01-28</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_2"><a class="anchor" href="#_new_features_and_enhancements_2"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Improved instructions on how to get cache hits between different working
directories.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_33"><a class="anchor" href="#_bug_fixes_33"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed regression in ccache 3.3.5 related to the <code>UNCACHED_ERR_FD</code> feature.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_5"><a class="anchor" href="#_ccache_3_3_5"></a>Ccache 3.3.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2018-01-13</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_3"><a class="anchor" href="#_new_features_and_enhancements_3"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Documented how automatic cache cleanup works.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_34"><a class="anchor" href="#_bug_fixes_34"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression where the original order of debug options could be lost.
This reverts the &#8220;Improved parsing of <code>-g*</code> options&#8221; feature in ccache 3.3.</p>
</li>
<li>
<p>Multiple <code>-fdebug-prefix-map</code> options should now be handled correctly.</p>
</li>
<li>
<p>Fixed matching of directories in the <code>ignore_headers_in_manifest</code>
configuration option.</p>
</li>
<li>
<p>Fixed detection of missing argument to <code>-opt</code>/<code>--options-file</code>.</p>
</li>
<li>
<p>ccache now bails out when building a precompiled header if any of the
corresponding header files has an updated timestamp. This fixes complaints
from Clang.</p>
</li>
<li>
<p>Fixed a bug related to erroneously storing a dependency file with absolute
paths in the cache on a preprocessed hit.</p>
</li>
<li>
<p><code>ccache -c/--cleanup</code> now works like documented: it just recalculates size
counters and trims the cache to not exceed the max size and file number
limits. Previously, the forced cleanup took &#8220;limit_multiple&#8221; into account,
so that <code>ccache -c/--cleanup</code> by default would trim the cache to 80% of the
max limit.</p>
</li>
<li>
<p>ccache no longer ignores linker arguments for Clang since Clang warns about
them.</p>
</li>
<li>
<p>Plugged a couple of file descriptor leaks.</p>
</li>
<li>
<p>Fixed a bug where ccache would skip hashing the compiler argument following a
<code>-fno-working-directory</code>, <code>-fworking-directory</code>, <code>-nostdinc</code>, <code>-nostdinc++</code>,
<code>-remap</code> or <code>-trigraphs</code> option in preprocessor mode.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_4"><a class="anchor" href="#_ccache_3_3_4"></a>Ccache 3.3.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2017-02-17</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_4"><a class="anchor" href="#_new_features_and_enhancements_4"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Documented the different cache statistics counters.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_35"><a class="anchor" href="#_bug_fixes_35"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression in ccache 3.3 related to potentially bad content of
dependency files when compiling identical source code but with different
source paths. This was only partially fixed in 3.3.2 and reverts the new
&#8220;Names of included files are no longer included in the hash of the compiler&#8217;s
preprocessed output&#8221; feature in 3.3.</p>
</li>
<li>
<p>Corrected statistics counter for <code>-optf</code>/<code>--options-file</code> failure.</p>
</li>
<li>
<p>Fixed undefined behavior warnings in ccache found by <code>-fsanitize=undefined</code>.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_3"><a class="anchor" href="#_ccache_3_3_3"></a>Ccache 3.3.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-10-26</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_36"><a class="anchor" href="#_bug_fixes_36"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>ccache now detects usage of <code>.incbin</code> assembler directives in the source code
and avoids caching such compilations.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_2"><a class="anchor" href="#_ccache_3_3_2"></a>Ccache 3.3.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-09-28</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_37"><a class="anchor" href="#_bug_fixes_37"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression in ccache 3.3 related to potentially bad content of
dependency files when compiling identical source code but with different
source paths.</p>
</li>
<li>
<p>Fixed a regression in ccache 3.3.1: ccache could get confused when using the
compiler option <code>-Wp,</code> to pass multiple options to the preprocessor,
resulting in missing dependency files from direct mode cache hits.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3_1"><a class="anchor" href="#_ccache_3_3_1"></a>Ccache 3.3.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-09-07</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_38"><a class="anchor" href="#_bug_fixes_38"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a problem in the &#8220;multiple <code>-arch</code> options&#8221; support introduced in 3.3.
When using the direct mode (the default), different combinations of <code>-arch</code>
options were not detected properly.</p>
</li>
<li>
<p>Fixed an issue when compiler option <code>-Wp,-MT,path</code> is used instead of <code>-MT
path</code> (and similar for <code>-MF</code>, <code>-MP</code> and <code>-MQ</code>) and <code>run_second_cpp</code>
(<code>CCACHE_CPP2</code>) is enabled.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_3"><a class="anchor" href="#_ccache_3_3"></a>Ccache 3.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-08-27</p>
</div>
<div class="sect2">
<h3 id="_notes"><a class="anchor" href="#_notes"></a>Notes</h3>
<div class="ulist">
<ul>
<li>
<p>A C99-compatible compiler is now required to build ccache.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_5"><a class="anchor" href="#_new_features_and_enhancements_5"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>The configuration option <code>run_second_cpp</code> (<code>CCACHE_CPP2</code>) now defaults to
true. This improves ccache&#8217;s out-of-the-box experience for compilers that
can&#8217;t compile their own preprocessed output with the same outcome as if they
compiled the real source code directly, e.g. newer versions of GCC and Clang.</p>
</li>
<li>
<p>The configuration option <code>hash_dir</code> (<code>CCACHE_HASHDIR</code>) now defaults to true.</p>
</li>
<li>
<p>Added a new <code>ignore_headers_in_manifest</code> configuration option, which
specifies headers that should be ignored in the direct mode.</p>
</li>
<li>
<p>Added a new <code>prefix_command_cpp</code> (<code>CCACHE_PREFIX_CPP</code>) configuration option,
which specifies one or several prefixes to add to the command line ccache
uses when invoking the preprocessor.</p>
</li>
<li>
<p>Added a new <code>limit_multiple</code> (<code>CCACHE_LIMIT_MULTIPLE</code>) configuration option,
which specifies how much of the cache to remove when cleaning.</p>
</li>
<li>
<p>Added a new <code>keep_comments_cpp</code> (<code>CCACHE_COMMENTS</code>) configuration option,
which tells ccache not to discard the comments before hashing preprocessor
output. This can be used to check documentation with <code>-Wdocumentation</code>.</p>
</li>
<li>
<p>Added a new sloppiness option <code>no_system_headers</code>, which tells ccache not to
include system headers in manifest files.</p>
</li>
<li>
<p>Added a new statistics counter that tracks the number of performed cleanups
due to the cache size being over the limit. The value is shown in the output
of &#8220;ccache -s&#8221;.</p>
</li>
<li>
<p>Added support for relocating debug info directory using <code>-fdebug-prefix-map</code>.
This allows for cache hits even when <code>hash_dir</code> is used in combination with
<code>base_dir</code>.</p>
</li>
<li>
<p>Added a new &#8220;cache hit rate&#8221; field to the output of &#8220;ccache -s&#8221;.</p>
</li>
<li>
<p>Added support for caching compilation of assembler code produced by e.g. &#8220;gcc
-S file.c&#8221;.</p>
</li>
<li>
<p>Added support for cuda including the -optf/--options-file option.</p>
</li>
<li>
<p>Added support for Fortran 77.</p>
</li>
<li>
<p>Added support for multiple <code>-arch</code> options to produce &#8220;fat binaries&#8221;.</p>
</li>
<li>
<p>Multiple identical <code>-arch</code> arguments are now handled without bailing.</p>
</li>
<li>
<p>The concatenated form of some long compiler options is now recognized, for
example when using <code>-isystemPATH</code> instead of <code>-isystem PATH</code>.</p>
</li>
<li>
<p>If hard-linking is enabled and but fails (e.g. due to cross-device linking),
ccache now falls back to copying instead of running the compiler.</p>
</li>
<li>
<p>Made the <code>hash_dir</code> option only have effect when generating debug info.</p>
</li>
<li>
<p>ccache now knows how to convert absolute paths to relative paths inside
dependency files when using <code>base_dir</code>.</p>
</li>
<li>
<p>Improved parsing of <code>-g*</code> options.</p>
</li>
<li>
<p>Made ccache understand <code>-Wp,-D*</code> options.</p>
</li>
<li>
<p>ccache now understands the undocumented <code>-coverage</code> (only one dash) GCC
option.</p>
</li>
<li>
<p>Names of included files are no longer included in the hash of the compiler&#8217;s
preprocessed output. This leads to more potential cache hits when not using
the direct mode.</p>
</li>
<li>
<p>Increased buffer size used when reading file data. This improves performance
slightly.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_39"><a class="anchor" href="#_bug_fixes_39"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Bail out on too hard compiler option <code>-P</code>.</p>
</li>
<li>
<p>Fixed Clang test suite when running on Linux.</p>
</li>
<li>
<p>Fixed build and test for MinGW32 and Windows.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_9"><a class="anchor" href="#_ccache_3_2_9"></a>Ccache 3.2.9</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-09-28</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_40"><a class="anchor" href="#_bug_fixes_40"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a regression in ccache 3.2.8: ccache could get confused when using the
compiler option <code>-Wp,</code> to pass multiple options to the preprocessor,
resulting in missing dependency files from direct mode cache hits.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_8"><a class="anchor" href="#_ccache_3_2_8"></a>Ccache 3.2.8</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-09-07</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_41"><a class="anchor" href="#_bug_fixes_41"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed an issue when compiler option <code>-Wp,-MT,path</code> is used instead of <code>-MT
path</code> (and similar for <code>-MF</code>, <code>-MP</code> and <code>-MQ</code>) and <code>run_second_cpp</code>
(<code>CCACHE_CPP2</code>) is enabled.</p>
</li>
<li>
<p>ccache now understands the undocumented <code>-coverage</code> (only one dash) GCC
option.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_7"><a class="anchor" href="#_ccache_3_2_7"></a>Ccache 3.2.7</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-07-20</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_42"><a class="anchor" href="#_bug_fixes_42"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a bug which could lead to false cache hits for compiler command lines
with a missing argument to an option that takes an argument.</p>
</li>
<li>
<p>ccache now knows how to work around a glitch in the output of GCC 6&#8217;s
preprocessor.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_6"><a class="anchor" href="#_ccache_3_2_6"></a>Ccache 3.2.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-07-12</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_43"><a class="anchor" href="#_bug_fixes_43"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed build problem on QNX, which lacks &#8220;SA_RESTART&#8221;.</p>
</li>
<li>
<p>Bail out on compiler option <code>-fstack-usage</code> since it creates a <code>.su</code> file
which ccache currently doesn&#8217;t handle.</p>
</li>
<li>
<p>Fixed a bug where (due to ccache rewriting paths) the compiler could choose
incorrect include files if <code>CCACHE_BASEDIR</code> is used and the source file path
is absolute and is a symlink.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_5"><a class="anchor" href="#_ccache_3_2_5"></a>Ccache 3.2.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-04-17</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_6"><a class="anchor" href="#_new_features_and_enhancements_6"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Only pass Clang-specific <code>-stdlib=</code> to the preprocessor.</p>
</li>
<li>
<p>Improved handling of stale NFS handles.</p>
</li>
<li>
<p>Made it harder to misinterpret documentation of boolean environment settings'
semantics.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_44"><a class="anchor" href="#_bug_fixes_44"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Include m4 files used by configure.ac in the source dist archives.</p>
</li>
<li>
<p>Corrected &#8220;Performance&#8221; section in the manual regarding <code><em>_DATE</em></code>,
<code>__TIME__</code> and <code>__FILE__</code> macros.</p>
</li>
<li>
<p>Fixed build on Solaris 10+ and AIX 7.</p>
</li>
<li>
<p>Fixed failure to create directories on QNX.</p>
</li>
<li>
<p>Don&#8217;t (try to) update manifest file in &#8220;read-only&#8221; and &#8220;read-only direct&#8221;
modes.</p>
</li>
<li>
<p>Fixed a bug in caching of <code>stat</code> system calls in &#8220;file_stat_matches
sloppiness mode&#8221;.</p>
</li>
<li>
<p>Fixed bug in hashing of Clang plugins, leading to unnecessary cache misses.</p>
</li>
<li>
<p>Fixed --print-config to show &#8220;pch_defines sloppiness&#8221;.</p>
</li>
<li>
<p>The man page is now built when running &#8220;make install&#8221; from Git repository
sources.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_4"><a class="anchor" href="#_ccache_3_2_4"></a>Ccache 3.2.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2015-10-08</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_45"><a class="anchor" href="#_bug_fixes_45"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed build error related to zlib on systems with older make versions
(regression in ccache 3.2.3).</p>
</li>
<li>
<p>Made conversion-to-bool explicit to avoid build warnings (and potential
runtime errors) on legacy systems.</p>
</li>
<li>
<p>Improved signal handling: Kill compiler on SIGTERM; wait for compiler to exit
before exiting; die appropriately.</p>
</li>
<li>
<p>Minor fixes related to Windows support.</p>
</li>
<li>
<p>The correct compression level is now used if compression is requested.</p>
</li>
<li>
<p>Fixed a bug where cache cleanup could be run too early for caches larger than
64 GiB on 32-bit systems.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_3"><a class="anchor" href="#_ccache_3_2_3"></a>Ccache 3.2.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2015-08-16</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_7"><a class="anchor" href="#_new_features_and_enhancements_7"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for compiler option <code>-gsplit-dwarf</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_46"><a class="anchor" href="#_bug_fixes_46"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Support external zlib in nonstandard directory.</p>
</li>
<li>
<p>Avoid calling <code>exit()</code> inside an exit handler.</p>
</li>
<li>
<p>Let exit handler terminate properly.</p>
</li>
<li>
<p>Bail out on compiler option <code>--save-temps</code> in addition to <code>-save-temps</code>.</p>
</li>
<li>
<p>Only log &#8220;Disabling direct mode&#8221; once when failing to read potential include
files.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_2"><a class="anchor" href="#_ccache_3_2_2"></a>Ccache 3.2.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2015-05-10</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_8"><a class="anchor" href="#_new_features_and_enhancements_8"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for <code>CCACHE_COMPILERCHECK=string:&lt;value&gt;</code>. This is a faster
alternative to <code>CCACHE_COMPILERCHECK=&lt;command&gt;</code> if the command&#8217;s output can
be precalculated by the build system.</p>
</li>
<li>
<p>Add support for caching code coverage results (compiling for gcov).</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_47"><a class="anchor" href="#_bug_fixes_47"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Made hash of cached result created with and without <code>CCACHE_CPP2</code> different.
This makes it possible to rebuild with <code>CCACHE_CPP2</code> set without having to
clear the cache to get new results.</p>
</li>
<li>
<p>Don&#8217;t try to reset a nonexistent stats file. This avoids &#8220;No such file or
directory&#8221; messages in the ccache log when the cache directory doesn&#8217;t exist.</p>
</li>
<li>
<p>Fixed a bug where ccache deleted Clang diagnostics after compiler failures.</p>
</li>
<li>
<p>Avoid performing an unnecessary copy of the object file on a cache miss.</p>
</li>
<li>
<p>Bail out on too hard compiler option <code>-fmodules</code>.</p>
</li>
<li>
<p>Bail out on too hard compiler option <code>-fplugin=libcc1plugin</code> (interaction
with GDB).</p>
</li>
<li>
<p>Fixed build error when compiling ccache with recent Clang versions.</p>
</li>
<li>
<p>Removed signal-unsafe code from signal handler.</p>
</li>
<li>
<p>Corrected logic for when to output cached stderr.</p>
</li>
<li>
<p>Wipe the whole cached result on failure retrieving a cached file.</p>
</li>
<li>
<p>Fixed build error when compiling ccache with recent Clang versions.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2_1"><a class="anchor" href="#_ccache_3_2_1"></a>Ccache 3.2.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2014-12-10</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_48"><a class="anchor" href="#_bug_fixes_48"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed regression in temporary file handling, which lead to incorrect
permissions for stats, manifest and ccache.conf files in the cache.</p>
</li>
<li>
<p><code>CACHEDIR.TAG</code> files are now created in the [0-9a-f] subdirectories so that
ccache.conf is not lost in backups.</p>
</li>
<li>
<p>Made the default cache size suffix <code>G</code>, as previously documented.</p>
</li>
<li>
<p><code>-fdiagnostics-color=auto</code> is now passed to the compiler even if stderr is
redirected. This fixes a problem when, for instance, a configure test probes
if the compiler (wrapped via ccache) supports <code>-fdiagnostics-color=auto</code>.</p>
</li>
<li>
<p>Added missing documentation for <code>max_files</code> and <code>max_size</code> configuration
options.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_2"><a class="anchor" href="#_ccache_3_2"></a>Ccache 3.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2014-11-17</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_9"><a class="anchor" href="#_new_features_and_enhancements_9"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for configuring ccache via one or several configuration files
instead of via environment variables. Environment variables still have
priority but are no longer the recommended way of customizing ccache
behavior. See the manual for more information.</p>
</li>
<li>
<p>Added support for compiler error/warning messages with color.</p>
</li>
<li>
<p>Made creation of temporary directories and cache directories smarter to avoid
unnecessary <code>stat</code> calls.</p>
</li>
<li>
<p>Improved efficiency of the algorithm that scans for <code><em>_DATE</em></code> and <code>__TIME__</code>
tokens in the hashed source code.</p>
</li>
<li>
<p>Added support for several binaries (separated by space) in <code>CCACHE_PREFIX</code>.</p>
</li>
<li>
<p>The <code>-c</code> option is no longer passed to the preprocessor. This fixes problems
with Clang and Solaris&#8217;s C++ compiler.</p>
</li>
<li>
<p>ccache no longer passes preprocessor options like <code>-D</code> and <code>-I</code> to the
compiler when compiling preprocessed output. This fixes warnings emitted by
Clang.</p>
</li>
<li>
<p>Compiler options <code>-fprofile-generate</code>, <code>-fprofile-arcs</code>, <code>-fprofile-use</code> and
<code>-fbranch-probabilities</code> are now handled without bailing.</p>
</li>
<li>
<p>Added support for Clang&#8217;s <code>--serialize-diagnostic</code> option, storing the
diagnostic file (<code>.dia</code>) in the cache.</p>
</li>
<li>
<p>Added support for precompiled headers when using Clang.</p>
</li>
<li>
<p>Added support for Clang <code>.pth</code> (pretokenized header) files.</p>
</li>
<li>
<p>Changed the <code>-x</code> language option to use the new objective C standard for GCC
and Clang.</p>
</li>
<li>
<p>On a cache miss, ccache now instructs the compiler to create the object file
at the real destination and then copies the file into the cache instead of
the other way around. This is needed to support compiler options like
<code>-fprofile-arcs</code> and <code>--serialize-diagnostics</code>.</p>
</li>
<li>
<p>ccache now checks that included files' ctimes aren&#8217;t too new. This check can
be turned off by adding <code>include_file_ctime</code> to the &#8220;ccache sloppiness&#8221;
setting.</p>
</li>
<li>
<p>Added possibility to get cache hits based on filename, size, mtime and ctime
only. On other words, source code files are not even read, only stat-ed. This
operation mode is opt-in by adding <code>file_stat_matches</code> to the &#8220;ccache
sloppiness&#8221; setting.</p>
</li>
<li>
<p>The filename part of options like <code>-Wp,-MDfilename</code> is no longer included in
the hash since the filename doesn&#8217;t have any bearing on the result.</p>
</li>
<li>
<p>Added a &#8220;read-only direct&#8221; configuration setting, which is like the ordinary
read-only setting except that ccache will only try to retrieve results from
the cache using the direct mode, not the preprocessor mode.</p>
</li>
<li>
<p>The display and interpretation of cache size has been changed to use SI
units.</p>
</li>
<li>
<p>Default cache size is now 5 GB (was previously 1 GiB).</p>
</li>
<li>
<p>Added configuration option to set the compression level of compressed object
files in the cache.</p>
</li>
<li>
<p>Added support for <code>@file</code> and <code>-@file</code> arguments (reading options from a
file).</p>
</li>
<li>
<p><code>-Wl,</code> options are no longer included in the hash since they don&#8217;t affect
compilation.</p>
</li>
<li>
<p>Bail out on too hard compiler option <code>-Wp,-P</code>.</p>
</li>
<li>
<p>Optimized MD4 calculation code on little-endian systems.</p>
</li>
<li>
<p>Various improvements and fixes on win32.</p>
</li>
<li>
<p>Improved logging to the ccache log file.</p>
</li>
<li>
<p>Added <code>--dump-manifest</code> command-line option for debugging purposes.</p>
</li>
<li>
<p>Added <code>--with-bundled-zlib</code> configure option.</p>
</li>
<li>
<p>Upgraded bundled zlib to version 1.2.8.</p>
</li>
<li>
<p>Improved <code>dev.mk</code> to be more platform independent.</p>
</li>
<li>
<p>Made the test suite work with Clang and gcc-llvm on OS X.</p>
</li>
<li>
<p>Various other improvements of the test suite.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_49"><a class="anchor" href="#_bug_fixes_49"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Any previous <code>.stderr</code> is now removed from the cache when recaching.</p>
</li>
<li>
<p>Fixed an issue when handling the <code>-arch</code> compiler option with an argument.</p>
</li>
<li>
<p>Fixed race condition when creating the initial cache directory.</p>
</li>
<li>
<p>Fixed test suite failures when <code>CC</code> is a ccache-wrapped compiler.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_12"><a class="anchor" href="#_ccache_3_1_12"></a>Ccache 3.1.12</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2016-07-12</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_50"><a class="anchor" href="#_bug_fixes_50"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed a bug where (due to ccache rewriting paths) the compiler could choose
incorrect include files if <code>CCACHE_BASEDIR</code> is used and the source file path
is absolute and is a symlink.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_11"><a class="anchor" href="#_ccache_3_1_11"></a>Ccache 3.1.11</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2015-03-07</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_51"><a class="anchor" href="#_bug_fixes_51"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed bug which could result in false cache hits when source code contains
<code>'"'</code> followed by <code>" /*"</code> or <code>" //"</code> (with variations).</p>
</li>
<li>
<p>Made hash of cached result created with and without <code>CCACHE_CPP2</code> different.
This makes it possible to rebuild with <code>CCACHE_CPP2</code> set without having to
clear the cache to get new results.</p>
</li>
<li>
<p>Don&#8217;t try to reset a nonexistent stats file. This avoids &#8220;No such file or
directory&#8221; messages in the ccache log when the cache directory doesn&#8217;t exist.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_10"><a class="anchor" href="#_ccache_3_1_10"></a>Ccache 3.1.10</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2014-10-19</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_10"><a class="anchor" href="#_new_features_and_enhancements_10"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for the <code>-Xclang</code> compiler option.</p>
</li>
<li>
<p>Improved handling of exit code of internally executed processes.</p>
</li>
<li>
<p>Zero length object files in the cache are now rejected as invalid.</p>
</li>
<li>
<p>Bail out on option <code>-gsplit-dwarf</code> (since it produces multiple output files).</p>
</li>
<li>
<p>Compiler option <code>-fdebug-prefix-map</code> is now ignored (not part of the hash).
(The <code>-fdebug-prefix-map</code> option may be used in combination with
<code>CCACHE_BASEDIR</code> to reuse results across different directories.)</p>
</li>
<li>
<p>Added note in documentation that <code>--ccache-skip</code> currently does not mean
&#8220;don&#8217;t hash the following option&#8221;.</p>
</li>
<li>
<p>To enable support for precompiled headers (PCH), <code>CCACHE_SLOPPINESS</code> now also
needs to include the new <code>pch_defines</code> sloppiness. This is because ccache
can&#8217;t detect changes in the source code when only defined macros have been
changed.</p>
</li>
<li>
<p>Stale files in the internal temporary directory (<code>&lt;ccache_dir&gt;/tmp</code>) are now
cleaned up if they are older than one hour.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_52"><a class="anchor" href="#_bug_fixes_52"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed path canonicalization in <code>make_relative_path()</code> when path doesn&#8217;t
exist.</p>
</li>
<li>
<p>Fixed bug in <code>common_dir_prefix_length()</code>. This corrects the <code>CCACHE_BASEDIR</code>
behavior.</p>
</li>
<li>
<p>ccache no longer tries to create the cache directory when <code>CCACHE_DISABLE</code> is
set.</p>
</li>
<li>
<p>Fixed bug when reading manifests with a very large number of file info
entries.</p>
</li>
<li>
<p>Fixed problem with logging of current working directory.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_9"><a class="anchor" href="#_ccache_3_1_9"></a>Ccache 3.1.9</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2013-01-06</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_53"><a class="anchor" href="#_bug_fixes_53"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The EAGAIN signal is now handled correctly when emitting cached stderr
output. This fixes a problem triggered by large error outputs from the
compiler.</p>
</li>
<li>
<p>Subdirectories in the cache are no longer created in read-only mode.</p>
</li>
<li>
<p>Fixed so that ccache&#8217;s log file descriptor is not made available to the
compiler.</p>
</li>
<li>
<p>Improved error reporting when failing to create temporary stdout/stderr files
when executing the compiler.</p>
</li>
<li>
<p>Disappearing temporary stdout/stderr files are now handled gracefully.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_5"><a class="anchor" href="#_other_5"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed test suite to work on ecryptfs.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_8"><a class="anchor" href="#_ccache_3_1_8"></a>Ccache 3.1.8</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2012-08-11</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_11"><a class="anchor" href="#_new_features_and_enhancements_11"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Made paths to dependency files relative in order to increase cache hits.</p>
</li>
<li>
<p>Added work-around to make ccache work with buggy GCC 4.1 when creating a
pre-compiled header.</p>
</li>
<li>
<p>Clang plugins are now hashed to catch plugin upgrades.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_54"><a class="anchor" href="#_bug_fixes_54"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Fixed crash when the current working directory has been removed.</p>
</li>
<li>
<p>Fixed crash when stderr is closed.</p>
</li>
<li>
<p>Corrected a corner case when parsing backslash escapes in string
literals.</p>
</li>
<li>
<p>Paths are now correctly canonicalized when computing paths relative to the
base directory.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_6"><a class="anchor" href="#_other_6"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Made git version macro work when compiling outside of the source directory.</p>
</li>
<li>
<p>Fixed <code>static_assert</code> macro definition clash with GCC 4.7.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_7"><a class="anchor" href="#_ccache_3_1_7"></a>Ccache 3.1.7</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2012-01-08</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_55"><a class="anchor" href="#_bug_fixes_55"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Non-writable <code>CCACHE_DIR</code> is now handled gracefully when <code>CCACHE_READONLY</code> is
set.</p>
</li>
<li>
<p>Made failure to create files (typically due to bad directory permissions) in
the cache directory fatal. Previously, such failures were silently and
erroneously flagged as &#8220;compiler produced stdout&#8221;.</p>
</li>
<li>
<p>Both the <code>-specs=file</code> and <code>--specs=file</code> forms are now recognized.</p>
</li>
<li>
<p>Added recognition and hashing of GCC plugins specified with <code>-fplugin=file</code>.</p>
</li>
<li>
<p><code>CCACHE_COMPILERCHECK</code> now also determines how to hash explicit specs files
(<code>-specs=file</code>).</p>
</li>
<li>
<p>Added <code>CPATH</code>, <code>C_INCLUDE_PATH</code> and similar environment variables to the hash
to avoid false cache hits when such variables have changed.</p>
</li>
<li>
<p>Corrected log message when unify mode is enabled.</p>
</li>
<li>
<p>Reverted the GCC bug compatibility introduced in ccache 3.1.5 for <code>-MT</code>/<code>-MQ</code>
options with concatenated arguments. (The bug is fixed in recent GCC
versions.)</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_7"><a class="anchor" href="#_other_7"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Corrected license header for <code>mdfour.c</code>.</p>
</li>
<li>
<p>Improved documentation on how to fix bad object files in the cache.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_6"><a class="anchor" href="#_ccache_3_1_6"></a>Ccache 3.1.6</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2011-08-21</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_12"><a class="anchor" href="#_new_features_and_enhancements_12"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Rewrite argument to <code>--sysroot</code> if <code>CCACHE_BASEDIR</code> is used.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_56"><a class="anchor" href="#_bug_fixes_56"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Don&#8217;t crash if <code>getcwd()</code> fails.</p>
</li>
<li>
<p>Fixed alignment of &#8220;called for preprocessing&#8221; counter.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_5"><a class="anchor" href="#_ccache_3_1_5"></a>Ccache 3.1.5</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2011-05-29</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_13"><a class="anchor" href="#_new_features_and_enhancements_13"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added a new statistics counter named &#8220;called for preprocessing&#8221;.</p>
</li>
<li>
<p>The original command line is now logged to the file specified with
<code>CCACHE_LOGFILE</code>.</p>
</li>
<li>
<p>Improved error logging when system calls fail.</p>
</li>
<li>
<p>Added support for rewriting absolute paths in <code>-F</code>/<code>-iframework</code> GCC
options.</p>
</li>
<li>
<p>Improved order of statistics counters in <code>ccache -s</code> output.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_57"><a class="anchor" href="#_bug_fixes_57"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The <code>-MF</code>/<code>-MT</code>/<code>-MQ</code> options with concatenated argument are now handled
correctly when they are last on the command line.</p>
</li>
<li>
<p>ccache is now bug compatible with GCC for the <code>-MT</code>/<code>-MQ</code> options with
concatenated arguments.</p>
</li>
<li>
<p>Fixed a minor memory leak.</p>
</li>
<li>
<p>Systems that lack (and don&#8217;t need to be linked with) libm are now supported.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_4"><a class="anchor" href="#_ccache_3_1_4"></a>Ccache 3.1.4</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2011-01-09</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_58"><a class="anchor" href="#_bug_fixes_58"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Made a work-around for a bug in <code>gzputc()</code> in zlib 1.2.5.</p>
</li>
<li>
<p>Corrupt manifest files are now removed so that they won&#8217;t block direct mode
hits.</p>
</li>
<li>
<p>ccache now copes with file systems that don&#8217;t know about symbolic links.</p>
</li>
<li>
<p>The file handle is now correctly closed on write error when trying to create
a cache dir tag.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_3"><a class="anchor" href="#_ccache_3_1_3"></a>Ccache 3.1.3</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-11-28</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_59"><a class="anchor" href="#_bug_fixes_59"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The -MFarg, -MTarg and -MQarg compiler options (i.e, without space between
option and argument) are now handled correctly.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_8"><a class="anchor" href="#_other_8"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Portability fixes for HP-UX 11.00 and other less common systems.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_2"><a class="anchor" href="#_ccache_3_1_2"></a>Ccache 3.1.2</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-11-21</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_60"><a class="anchor" href="#_bug_fixes_60"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Bail out on too hard compiler options <code>-fdump-*</code>.</p>
</li>
<li>
<p>NULL return values from malloc/calloc of zero bytes are now handled
correctly.</p>
</li>
<li>
<p>Fixed issue when parsing precompiler output on AIX.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_9"><a class="anchor" href="#_other_9"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Improved documentation on which information is included in the hash sum.</p>
</li>
<li>
<p>Made the &#8220;too new header file&#8221; test case work on file systems with
unsynchronized clocks.</p>
</li>
<li>
<p>The test suite now also works on systems that lack a /dev/zero.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1_1"><a class="anchor" href="#_ccache_3_1_1"></a>Ccache 3.1.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-11-07</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_61"><a class="anchor" href="#_bug_fixes_61"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>ccache now falls back to preprocessor mode when a non-regular include file
(device, socket, etc) has been detected so that potential hanging due to
blocking reads is avoided.</p>
</li>
<li>
<p>CRC errors are now detected when decompressing compressed files in the cache.</p>
</li>
<li>
<p>Fixed potential object file corruption race on NFS.</p>
</li>
<li>
<p>Minor documentation corrections.</p>
</li>
<li>
<p>Fixed configure detection of ar.</p>
</li>
<li>
<p>ccache development version (set by dev.mk) now works with gits whose
<code>describe</code> command doesn&#8217;t understand <code>--dirty</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_10"><a class="anchor" href="#_other_10"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Minor debug log message improvements.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_1"><a class="anchor" href="#_ccache_3_1"></a>Ccache 3.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-09-16</p>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_14"><a class="anchor" href="#_new_features_and_enhancements_14"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>Added support for hashing the output of a custom command (e.g. <code>%compiler%
--version</code>) to identify the compiler instead of stat-ing or hashing the
compiler binary. This can improve robustness when the compiler (as seen by
ccache) actually isn&#8217;t the real compiler but another compiler wrapper.</p>
</li>
<li>
<p>Added support for caching compilations that use precompiled headers. (See the
manual for important instructions regarding this.)</p>
</li>
<li>
<p>Locking of the files containing statistics counters is now done using
symlinks instead of POSIX locks. This should make ccache behave a lot better
on file systems where POSIX locks are slow or broken (e.g. NFS on some
systems).</p>
</li>
<li>
<p>Manifest files are now updated without the need of taking locks.</p>
</li>
<li>
<p>Updates of statistics counters are now always done in one of the sub-level
statistics files. This reduces lock contention, which especially improves
performance on slow NFS mounts.</p>
</li>
<li>
<p>Reading and writing of statistics counters has been made forward-compatible
(unknown counters are retained).</p>
</li>
<li>
<p>Files are now read without using <code>mmap()</code>. This has two benefits: it&#8217;s more
robust against file changes during reading and it improves performance on
poor systems where <code>mmap()</code> doesn&#8217;t use the disk cache.</p>
</li>
<li>
<p>Added <code>.cp</code> and <code>.CP</code> as known C++ suffixes.</p>
</li>
<li>
<p>Improved logging.</p>
</li>
<li>
<p>Added <code>-install_name</code> as an option known to take an argument. (This improves
statistics when using the Darwin linker.)</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_62"><a class="anchor" href="#_bug_fixes_62"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Non-fatal error messages are now never printed to stderr but logged instead.</p>
</li>
<li>
<p>Fixed a bug affecting failing commands when <code>--ccache-skip</code> is used.</p>
</li>
<li>
<p>Made <code>--ccache-skip</code> work for all options.</p>
</li>
<li>
<p>EINTR is now handled correctly.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_other_11"><a class="anchor" href="#_other_11"></a>Other</h3>
<div class="ulist">
<ul>
<li>
<p>Work on porting ccache to win32 (native), mostly done by Ramiro Polla. The
port is not yet finished, but will hopefully be complete in some subsequent
release.</p>
</li>
<li>
<p>Added a <code>--nostats</code> flag to the performance benchmark program.</p>
</li>
<li>
<p>Made the performance benchmark program more accurate when measuring cache
hits.</p>
</li>
<li>
<p>Added a new test framework for unit tests written in C.</p>
</li>
<li>
<p>Got rid of <code>configure-dev</code>; dev mode is now given by <code>dev.mk.in</code> presence.</p>
</li>
<li>
<p>Improved documentation on how to combine ccache with other compiler wrappers
(like <code>distcc</code>).</p>
</li>
<li>
<p>New <code>LICENSE.txt</code> file with licensing and copyright details about bundled
source code.</p>
</li>
<li>
<p>New <code>AUTHORS.txt</code> file with a list of ccache contributors.</p>
</li>
<li>
<p>New <code>HACKING.txt</code> file with some notes about ccache code conventions.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_0_1"><a class="anchor" href="#_ccache_3_0_1"></a>Ccache 3.0.1</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-07-15</p>
</div>
<div class="sect2">
<h3 id="_bug_fixes_63"><a class="anchor" href="#_bug_fixes_63"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>The statistics counter &#8220;called for link&#8221; is now correctly updated when
linking with a single object file.</p>
</li>
<li>
<p>Fixed a problem with out-of-source builds.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
<div class="sect1">
<h2 id="_ccache_3_0"><a class="anchor" href="#_ccache_3_0"></a>Ccache 3.0</h2>
<div class="sectionbody">
<div class="paragraph">
<p>Release date: 2010-06-20</p>
</div>
<div class="sect2">
<h3 id="_general"><a class="anchor" href="#_general"></a>General</h3>
<div class="ulist">
<ul>
<li>
<p>ccache is now licensed under the GNU General Public License (GPL) version 3
or later.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_upgrade_notes"><a class="anchor" href="#_upgrade_notes"></a>Upgrade notes</h3>
<div class="ulist">
<ul>
<li>
<p>The way the hashes are calculated has changed, so you won&#8217;t get cache hits
for compilation results stored by older ccache versions. Because of this, you
might as well clear the old cache directory with <code>ccache --clear</code> if you
want, unless you plan to keep using an older ccache version.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_new_features_and_enhancements_15"><a class="anchor" href="#_new_features_and_enhancements_15"></a>New features and enhancements</h3>
<div class="ulist">
<ul>
<li>
<p>ccache now has a &#8220;direct mode&#8221; where it computes a hash of the source code
(including all included files) and compiler options without running the
preprocessor. By not running the preprocessor, CPU usage is reduced; the
speed is somewhere between 1 and 5 times that of ccache running in
traditional mode, depending on the circumstances. The speedup will be higher
when I/O is fast (e.g., when files are in the disk cache). The direct mode
can be disabled by setting CCACHE_NODIRECT.</p>
</li>
<li>
<p>Support has been added for rewriting absolute paths to relative paths when
hashing, in order to increase cache hit rate when building the same source
code in different directories even when compiling with <code>-g</code> and when using
absolute include directory paths. This is done by setting the
<code>CCACHE_BASEDIR</code> environment variable to an absolute path that specifies
which paths to rewrite.</p>
</li>
<li>
<p>Object files are now optionally stored compressed in the cache. The runtime
cost is negligible, and more files will fit in the ccache directory and in
the disk cache. Set <code>CCACHE_COMPRESS</code> to enable object file compression. Note
that you can&#8217;t use compression in combination with the hard link feature.</p>
</li>
<li>
<p>A <code>CCACHE_COMPILERCHECK</code> option has been added. This option tells ccache what
compiler-identifying information to hash to ensure that results retrieved
from the cache are accurate. Possible values are: none (don&#8217;t hash anything),
mtime (hash the compiler&#8217;s mtime and size) and content (hash the content of
the compiler binary). The default is mtime.</p>
</li>
<li>
<p>It is now possible to specify extra files whose contents should be included
in the hash sum by setting the <code>CCACHE_EXTRAFILES</code> option.</p>
</li>
<li>
<p>Added support for Objective-C and Objective-C\\. The statistics counter
&#8220;not a C/C++ file&#8221; has been renamed to &#8220;unsupported source language&#8221;.</p>
</li>
<li>
<p>Added support for the <code>-x</code> compiler option.</p>
</li>
<li>
<p>Added support for long command-line options.</p>
</li>
<li>
<p>A <code>CACHEDIR.TAG</code> file is now created in the cache directory. See
<a href="http://www.brynosaurus.com/cachedir/" class="bare">http://www.brynosaurus.com/cachedir/</a>.</p>
</li>
<li>
<p>Messages printed to the debug log (specified by <code>CCACHE_LOGFILE</code>) have been
improved.</p>
</li>
<li>
<p>You can relax some checks that ccache does in direct mode by setting
<code>CCACHE_SLOPPINESS</code>. See the manual for more information.</p>
</li>
<li>
<p><code>CCACHE_TEMPDIR</code> no longer needs to be on the same filesystem as
<code>CCACHE_DIR</code>.</p>
</li>
<li>
<p>The default value of <code>CCACHE_TEMPDIR</code> has been changed to <code>$CCACHE_DIR/tmp</code>
to avoid cluttering the top directory.</p>
</li>
<li>
<p>Temporary files that later will be moved into the cache are now created in
the cache directory they will end up in. This makes ccache more friendly to
Linux&#8217;s directory layout.</p>
</li>
<li>
<p>Improved the test suite and added tests for most of the new functionality.
It&#8217;s now also possible to specify a subset of tests to run.</p>
</li>
<li>
<p>Standard error output from the compiler is now only stored in the cache if
it&#8217;s non-empty.</p>
</li>
<li>
<p>If the compiler produces no object file or an empty object file, but gives a
zero exit status (could be due to a file system problem, a buggy program
specified by <code>CCACHE_PREFIX</code>, etc.), ccache copes with it properly.</p>
</li>
<li>
<p>Added <code>installcheck</code> and <code>distcheck</code> make targets.</p>
</li>
<li>
<p>Clarified cache size limit options' and cleanup semantics.</p>
</li>
<li>
<p>Improved display of cache max size values.</p>
</li>
<li>
<p>The following options are no longer hashed in the preprocessor mode:
<code>-imacros</code>, <code>-imultilib</code>, <code>-iprefix</code>, <code>-iquote</code>, <code>-isysroot</code>, <code>-iwithprefix</code>,
<code>-iwithprefixbefore</code>, <code>-nostdinc</code>, <code>-nostdinc++</code> and <code>-U</code>.</p>
</li>
</ul>
</div>
</div>
<div class="sect2">
<h3 id="_bug_fixes_64"><a class="anchor" href="#_bug_fixes_64"></a>Bug fixes</h3>
<div class="ulist">
<ul>
<li>
<p>Various portability improvements.</p>
</li>
<li>
<p>Improved detection of home directory.</p>
</li>
<li>
<p>User-defined <code>CPPFLAGS</code> and <code>LDFLAGS</code> are now respected in the Makefile.</p>
</li>
<li>
<p>Fixed NFS issues.</p>
</li>
<li>
<p>Computation of the hash sum has been improved to decrease the risk of hash
collisions. For instance, the compiler options <code>-X -Y</code> and <code>-X-Y</code> previously
contributed equally to the hash sum.</p>
</li>
<li>
<p>Bail out on too hard compiler options <code>--coverage</code>, <code>-fprofile-arcs</code>,
<code>-fprofile-generate</code>, <code>-fprofile-use</code>, <code>-frepo</code>, <code>-ftest-coverage</code> and
<code>-save-temps</code>. Also bail out on <code>@file</code> style options.</p>
</li>
<li>
<p>Errors when using multiple <code>-arch</code> compiler options are now noted as
&#8220;unsupported compiler option&#8221;.</p>
</li>
<li>
<p><code>-MD</code>/<code>-MMD</code> options without <code>-MT</code>/<code>-MF</code> are now handled correctly.</p>
</li>
<li>
<p>The <code>-finput-charset</code> option is now handled correctly.</p>
</li>
<li>
<p>Added support for <code>-Wp,-MD</code> and <code>-Wp,-MMD</code> options.</p>
</li>
<li>
<p>The compiler options <code>-Xassembler</code>, <code>-b</code>, <code>-G</code> and <code>-V</code> are now correctly
recognized as taking an argument.</p>
</li>
<li>
<p>Debug information containing line numbers of predefined and command-line
macros (enabled with the compiler option <code>-g3</code>) will now be correct.</p>
</li>
<li>
<p>Corrected LRU cleanup handling of object files.</p>
</li>
<li>
<p><code>utimes()</code> is now used instead of <code>utime()</code> when available.</p>
</li>
<li>
<p>Non-writable cache directories are now handled gracefully.</p>
</li>
<li>
<p>Corrected documentation about sharing the cache directory.</p>
</li>
<li>
<p>Fixed compilation warnings from GCC 4.3.</p>
</li>
<li>
<p>The command specified by <code>CCACHE_PREFIX</code> is no longer part of the hash.</p>
</li>
<li>
<p>Fixed bad memory access spotted by Valgrind.</p>
</li>
<li>
<p>Fixed a bug in <code>x_realloc</code>.</p>
</li>
<li>
<p>Freed memory is no longer referenced when compiling a <code>.i</code>/<code>.ii</code> file and
falling back to running the real compiler.</p>
</li>
<li>
<p>The test suite is now immune to external values of the <code>CCACHE_*</code> environment
variables.</p>
</li>
<li>
<p>Improved detection of recursive invocation.</p>
</li>
<li>
<p>The ccache binary is now not unconditionally stripped when installing.</p>
</li>
<li>
<p>Statistics counters are now correctly updated for -E option failures and
internal errors.</p>
</li>
</ul>
</div>
</div>
</div>
</div>
</div>
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